The amount of a radioactive substance remaining after t years is given by the function , where m is the initial mass and h is the half-life in years. Cobalt-60 has a half-life of about 5. 3 years. Which equation gives the mass of a 50 mg Cobalt-60 sample remaining after 10 years, and approximately how many milligrams remain? ; 13. 5 mg ; 34. 6 mg ; 0. 2 mg ; 4. 6 mg.

Answers

Answer 1

Given that the amount of a radioactive substance remaining after t years is given by the function

[tex]$m(t) = m \left(\frac{1}{2}\right)^{\frac{t}{h}}$[/tex]

where m is the initial mass and h is the half-life in years.

Now, Cobalt-60 has a half-life of about 5.3 years.

If the initial mass is 50mg,

then the equation gives the mass of a 50 mg Cobalt-60 sample remaining after 10 years is

[tex]$m(10) = 50 \left(\frac{1}{2}\right)^{\frac{10}{5.3}} = 50 \left(\frac{1}{2}\right)^{\frac{20}{10.6}} = 50 \left(\frac{1}{2}\right)^{1.88} \approx 13.5$[/tex] milligrams.

So, approximately 13.5 milligrams remain.

Therefore, the correct option is 13.5 mg.

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Related Questions

For the given equation, find the values of a, b, and c, determine the direction in which the parabola opens, and determine the y-intercept. Decide which table best illustrates these values for the equation: f (x) = negative 9 x squared + 7 x.

Answers

Examining the function  -9x² + 7x the parabolic curve is opening downwards and the y intercept is 7/9 and 0

Where to look for the y intercepts

The sign of the x2 coefficient determines whether a parabolic curve opens upward or downward in this scenario.

In this function, the coefficient of x2 is a and is -9.

Rising downwards results from a negative coefficient, while opening upwards from a positive coefficient

The intercept of y

-9x² + 7x = 0

x(-9x + 7) = 0

x = 0

-9x + 7 = 0

-9x = -7

x = 7/9

Therfore, Examining the function  -9x² + 7x ,  0 and 7/9 is the y intercept.

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Find the coordiantes of the vertices for the figure after the given transformation
Dilation of 0.25.

Answers

Answer:

[tex]I'(-0.5,0.25), J'(0.5,0.5), K'(0.5, -0.25)[/tex]

Step-by-step explanation:

Assuming the dilation is centered at the origin, we can use the rule that:

For a dilation of scale factor [tex]k[/tex] centered at the origin, [tex](x,y) \to (kx,ky)[/tex]

What is the formula of area and perimeter of triangle?

Answers

Answer: area: 1/2 length * width, perimeter: add the three sides

Step-by-step explanation:

How do you find the pattern rule of a sequence?

Answers

An example of a pattern rule is "add 3" which means that to find the next term in a sequence, you add 3 to the previous term.

To write a rule for a sequence, you need to identify the pattern. This involves looking at the differences between the numbers and seeing if there is a pattern of increasing or decreasing numbers. Once you have identified the pattern, you can then write a rule that expresses that pattern.

Examples of pattern sequences include the Fibonacci sequence (1,1,2,3,5,8,13,21,34, etc.), the even numbers (2,4,6,8,10, etc.), and the multiples of 3 (3,6,9,12,15, etc.).

To describe the pattern of a sequence, you need to look at the differences between the numbers and the pattern of increases or decreases. For example, in the Fibonacci sequence, the pattern is that each number is the sum of the two numbers before it so 1+1=2, 1+2=3, 2+3=5, etc.

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Evaluate the expression: 5 + 3 × (5 - 2) 2

32
72
36
16

Answers

I swear it was 23??im pretty sure it was.

Select all the tranformation that apply to thi quadratic function:

y=1/3(x2)24

Answers

The transformations that apply are Horizontal stretch or compression by a factor of 3, Vertical shift up by 24 units, Reflection over the x-axis, The leading coefficient of 1/3 is a vertical compression and The exponent of 2 on x is a parabola.

Vertical Stretch/Compression by a factor of 3: The coefficient in front of the x^2 term is 1/3, which stretches or compresses the graph vertically by a factor of 3.

Horizontal Stretch/Compression by a factor of 24: The exponent on the x term is 24, which stretches or compresses the graph horizontally by a factor of 24.

Reflect over the x-axis: The coefficient in front of the x^2 term is positive, so the graph is reflected over the x-axis.

Shift up or down: The constant term is not present, so the graph does not shift up or down.

Shift left or right: The constant term is not present, so the graph does not shift left or right.

Rotation: The graph does not rotate as it is a parabola in the standard form y=ax^2 + bx + c, it does not have any trigonometric function in it.

Therefore, The transformations that apply are Horizontal stretch or compression by a factor of 3, Vertical shift up by 24 units, Reflection over the x-axis, The leading coefficient of 1/3 is a vertical compression and The exponent of 2 on x is a parabola.

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help!
is this correct?

Answers

Answer:3/4

Step-by-step explanation:

1/4 multiplied 3/1 =3/4

(4n^4-7n^3-29n^2-29n+4)/(n-4) Synthetic Division

Answers

Answer:1111

Step-by-step explanation:

11111

URGENT! Write an expression that represents the volume of the nth chamber. Explain your reasoning.

Answers

The volume of the chamber follows a pattern. The formula that represents the volume of the nth chamber is 6.3% of the previous chamber.

What is a pattern?

A pattern is a repeated arrangement of numbers, shapes, colours, or other elements. The Pattern can be associated with any kind of event or object. A pattern is defined as a set of numbers that are related to one another in a specific way. Patterns are sometimes referred to as sequences.

Given that:

Chamber 7: 1.207 cm³

Chamber 6: 1.135 cm³

Chamber 5: 1.068 cm³

Chamber 4: 1.005 cm³

Chamber 3: 0.945 cm³

Chamber 2: 0.889 cm³

Chamber 2: 0.836 cm³

                          1.207     1.135     1.068   1.005     0.945      0.889      0.836

First difference:        .072        0.067    0.063   0.060    0.056      0.053

Second difference:            0.005     0.004    0.003     0.004    0.003

Since the difference is not the same, thus the volume is not in a linear pattern. Then find the ratio consecutive volume:

1.207/1.135 ≈ 1.063

1.135/1.068 ≈ 1.063

1.068/1.005 ≈ 1.063

1.005/0.945 ≈ 1.063

0.945/0.889 ≈ 1.063

0.889/0.836 ≈ 1.063

Each chamber is 6.3% greater than the previous chamber. The pattern is exponential functions.

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How do you fill a table with a function?

Answers

The proper method of filling a table with a function has been explained below.

Tables are helpful when we have to plot a function or we have to interpolate a function using given data points. A table usually consists of 2 or more 2 variables whose values are arranged either in a row or in a column. For filling a table with the help of a function, firstly we have to define the values of independent variables which we will input into the function to get the dependent variable's values.

When we get the value of independent data we will be inputting one of one those values in the function we will get the values of the function at the given point and hence the function will be filled by the output values.

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100 POINTS!! I need this now here is the text version

Two ocean beaches are being affected by erosion. The table shows the width, in feet, of each beach measured at high tide where 1995 is represented by year 0:

Year number Western Beach width (in feet) Dunes Beach width (in feet)
0 100 20
5 90 45
10 80 70
11 78 75
12 76 80
15 70 95

Describe the patterns shown by the erosion data measurements shown for each of the beaches in the table.
Between which years will the beaches have approximately the same width?
Assuming these rates remain constant, what can you do to get a better approximation of when the two beaches will have the same width?

Answers

The pattern shown by the erosion data measurements for the Western Beach is that the width decreases over time, with a steady decrease of about 10 feet per year. The pattern for the Dunes Beach is that the width increases over time, with an increase of about 5 feet per year.

Based on the data, it appears that the beaches will have approximately the same width around year 20. At this point, the Western Beach will have a width of approximately 50 feet and the Dunes Beach will have a width of approximately 90 feet.

To get a better approximation of when the two beaches will have the same width, it would be necessary to gather more data points over a longer period of time and to take into account other factors that may affect the beaches' widths such as the strength of the waves, the composition of the beach, and human interventions that may be taking place.

What is the degree of the polynomial 2x2?

Answers

In this case, the highest power on any variable is 2. As a result, the degree of polynomial is 2.

What is degree of the polynomial?

The degree of a polynomial in mathematics is the highest of the degrees of the polynomial's monomials with non-zero coefficients. A term's degree is the sum of the exponents of the variables in it, and it is thus a non-negative integer. The degree of a polynomial is the greatest or maximum power of a variable in a polynomial equation. A degree represents the polynomial with the greatest exponential power. Finding the degree of a polynomial. 2 x 2 + 2 x - 364 = 0. The maximum degree of the polynomial in the preceding equation.

Here,

Given : 2x^2

Degree of polynomial = Highest power of a variable.

Here, 2 is the highest power on any variable. So, degree of polynomial is 2.

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Jordan plotted the graph below to show the relationship between the temperature of his city and the number of cups of hot chocolate he sold daily.

Part A: In your own words, describe the relationship between the temperature the city and the number cups hot chocolate sold.

Part B: Describe how you can make the line of best fit. Write the approximate slope and y-intercept the line best fit. Show your work, including the points that you use to calculate the slope and y-intercept

Answers

Every 10 degrees higher in temperature, the slope would be around -3 so draw a line from (40,20) to (80,8) .

what is slope ?

How steep a line is defined by its slope. Gradient overflow is a term used to describe a gradient-based mathematical equation (the change in y divided by the change in x). The slope is calculated by dividing the horizontal change (run) between two points by the vertical change (rise) between the same two points. The slope-intercept form of an equation is used to express the equation of a straight line, which is written as y = mx + b. The line's y-intercept is situated where the slope is m, b is b, and (0, b). For instance, the slope and y-intercept of the equation y = 3x - 7 (0, 7).

givenI won't use (40,2) because it is an extreme case.

If I were to draw a line from those points, I would roughly estimate that it would have the same number of dots above and below the line, indicating that it is a line of best fit.

Every 10 degrees higher in temperature, the slope would be around -3 so draw a line from (40,20) to (80,8) .

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. Which ordered pairs in the form (x, y) are solutions to the equation 7x – 5y = 28?
Choose all answers that are correct.
A. (−6, −14)
B. (−1, −7)
C. (4, 10)
D. (7, 9)

Answers

Answer:

A and B

Step-by-step explanation:

to determine which pairs are solutions , substitute the x and y coordinates into the left side of the equation and if equal to the right side then solution.

A (- 6, - 14 )

7(- 6) - 5(- 14) = - 42 + 70 = 28 ← true , so solution

B (- 1, - 7 )

7(- 1) - 5(- 7) = - 7 + 35 = 28 ← true , so solution

C (4, 10 )

7(4) - 5(10) = 28 - 50 = - 22 ≠ 28 , not a solution

D (7, 9 )

7(7) - 5(9) = 49 - 45 = 4 ≠ 28 , not a solution

Balance the following equation: CCl4 --> C + Cl2

Answers

The balanced equation is:

CCl₄ --> C + 2Cl₂

Define term term balancing of chemical equation?

The law of conservation of mass states that when a chemical reaction takes place, the mass of the reactants and products should be equal.

As a result, during the chemical process, the number of atoms for each element remains constant. The chemical equation which it depicts the chemical reaction must be balanced as a result. When the total number of atoms found in the reactants and products sides of a chemical equation equals one, the equation is said to be balanced.

Here is an equation that describes a chemical reaction:

CCl₄ --> C + 2Cl₂

Reactant =  1 atom of C and 4 atoms of Cl.Product = 1 atom of C and 2 atoms of Cl.

Thus, add 2 atoms of Cl to balance the equation.

Then,

The balanced equation is:

CCl₄ --> C + 2Cl₂

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28. From the four numbers below, Maria chose one number. The number is even and none of its digits are the same. The hundreds digit is triple the ones digit. The tens digit is greater than the thousands digit. Which number did Maria choose? A. 3672 B. 4983 C. 2682 D. 8462​

Answers

Answer:

Maria chose C. 2682

Step-by-step explanation:

On a standardized test with a normal distribution, the mean
is 20 and the standard deviation is 2.6. In which interval
would the greatest number of scores occur?

Answers

Answer: The interval in which the greatest number of scores would occur is between (20 - 2.6) and (20 + 2.6), which is approximately 17.4 and 22.6 respectively. This interval is also known as the "bell curve" or the "normal distribution curve" and it is centered at the mean (20) and covers approximately 68% of all possible scores. Most of the data points would fall within one standard deviation of the mean, hence the greatest number of scores would occur in this interval.

Step-by-step explanation:

Question 1 (Multiple Choice Worth 1 points)
(03.01 MC)
Simplify √5 (8+3√6).
8√5 +3√30
O 5√10
130
O√40+15√6

Answers

So, the answer after simplifying the given square root equation is 8√5 + 3√30.

Define square.

A square has four equal sides, and four vertices, and is a closed, two-dimensional object. It has parallel sides on either side. A square is also equivalent to a rectangle with equal length and width.

What are vertices?

A vertex is a location in geometry where two or more curves, lines, or edges converge. As a result of this definition, vertices are the intersection of two lines that create an angle as well as the corners of polygons and polyhedra.

Solving,

√5 (8+3√6)

= √5 * 8 + √5 * 3√6

= 8 * √5 + √5 * 3√6

= 8√5 + 3√5*6

= 8√5 + 3√30

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what are the excluded factors of 2/x+3

Answers

Answer:

x=3

Step-by-step explanation:

An equation's omitted factors are the values of x for which the result is unknown. This indicates that if the denominator or x(x-3) equals 0, your solution is undefined.

Set up this equation and solve for the potential possibilities of x to find these numbers: x(x-3)=0

Divide both sides by (x-3) to find one of the values:

x(x-3)/(x-3)=0(x-3)

Because (x-3) cancels on the left side of the equation and everything divided by 0 is zero on the right, you should get: x=0.

Now that you've determined one of the excluded values, work out the other:

To begin, split both sides by x:

x(x-3)=0

x-3=0

Finally, multiply both sides by -3 to get: x=3

I need help on yo expand and simplify

Answers

After simplification, the formula 4 (2x - 1) + 3 (2x + 5) becomes 14x + 11.

How does expanded form work?

A number's arithmetic value for each digit can be expressed using the expanding form. Expanded numbers are numerical expressions that consist of the place value of each digit added to the total of the digits. To improve place value comprehension, expanded form is an excellent strategy.

It is given that,

4 (2x - 1) + 3 (2x + 5)

We have to expand and simplify the expression,

= 4 (2x - 1) + 3 (2x + 5)

Multiply the term out of the bracket into the bracket as

= 8x - 4 + 6x + 15

Add comparable terms together so that we can execute mathematical operations like addition and subtraction on the result.

= 14x + 11

As a result, the simplified expression for 4 (2x - 1) + 3 (2x + 5) will be 14x + 11.

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PLEASE!!!! I NEED HELP WITH MY HOMEWORK!!!!!!
(GEOMETRY)!!!

Answers

Answer:N= 10 fo sho m -14 maybe

Step-by-step explanation:

this triangle is an isosceles triangle because of the 90 45 45 angles. This means that the two side lengths are equal and 10 is equal to n. to calculate m is maybe square root of 2 times 10 because this image.

PLEASE HELP FIND X
1/2 (2x - 4) + 2 = 4(x + 2) - 11

Answers

Here’s step by step work:

What does an r value of 0.3 mean?

Answers

Low positive correlation :)

how much does the job pay in a 8hour day if they have 5 employees working $25 a hr

Answers

Answer:

1000$

Step-by-step explanation:

1000$

HELP MEEEEEEEEE PLEASEEE

Answers

The coordinates of the points after the translation are:

Q'  = (5, 4)R'  = (6, 1)

What are the coordinates of Q' and R'?

All the points are translated on the same way, so let's analyze the translation of P to P'.

The coordinates of Pare (5, 8), and P' is at (3, 4)

Then the translation is:

(3, 4) - (5, 8) = (3 - 5, 4 - 8) = (-2, -4)

So we just need to subtract 2 to the x-value and 4 to the y-value.

The coordinates of Q and R are:

Q = (7, 8)

R = (8, 5)

Then the translated points are:

Q' = (7 - 2,8 - 4) = (5, 4)

R' = (8 - 2, 5 - 4) = (6, 1)

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Find the coordinates of the vertices of the figure after the given transformation.

Dilation of 0.25

Answers

Answer:

Option 3

Step-by-step explanation:

Assuming the dilation is centered at the origin, it is known that for a dilation of scale factor [tex]k[/tex] centered at the origin, [tex](x,y) \to (kx,ky)[/tex].

After dilation of with a scale factor of 0.25 the pre image coordinates

V (1,  1), W (2, -2) T ( 4, 2) and U(3, 3) transformed to

V' (0.25, 0.25)

W' (0.5, -0.5)

T' (1, 0.5)

U' (0.75, 0.75)

How to find the coordinates after dilation

Dilation is a method of transformation that magnify or shrink the preimage depending on the scale factor

In dilation, transformation rule is as follows

(x, y) for a scale factor of r → (rx, ry)

following similar the rule for r = 0.25 we have

preimage                                       image

V (1,  1)   → (0.25 * 1, 0.25 * 1)  →   V' (0.25, 0.25)

W (2, 2)   → (0.25 * 2, 0.25 * -2) →  W' (0.5, -0.5)

T (4, 2)   → (0.25 * 4, 0.25 * 2) →   T' (1, 0.5)

U (3, 3)   → (0.25 * 3, 0.25 * 3) →   U' (0.75, 0.75)

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Help, needed ASAP Thank you!!

Answers

Answer:

∠S = 105°

∠T = 95°

Step-by-step explanation:

Cyclic quadrilateral:

   Quadrilateral MNST is a cyclic quadrilateral. In cyclic quadrilateral, the opposite angles are supplementary.

     m∠S + m∠M = 180°

 3x + 2x +  5 = 180

        5x  + 5  = 180           {Combine like terms}

                 5x = 180 - 5     {Subtract 5 from both sides}

                 5x = 175

                    x = 175 ÷ 5  {Divide both sides by 5}

                    x = 35°

∠S = 3x

    = 3 * 35

    = 105°

∠T = 3x - 10

     = (3*35) - 10

     = 105 - 10

     = 95°

How do you find the area of a triangle with 3 vectors?

Answers

The  area of the triangle is equal to: Area = (|A| x |B| x sin(θ))/2

To calculate the area of a triangle with 3 vectors, we will use the vector triple product formula. This formula states that the area of the triangle is equal to the magnitude of the cross product of two of the vectors divided by two.

Let's say we have three vectors A, B, and C. The area of the triangle is then equal to the magnitude of the cross product of vector A and B, divided by two.

The magnitude of the cross product of A and B can be calculated as follows:

Magnitude of (A x B) = |A| x |B| x sin(θ)

Where |A| and |B| are the magnitudes of vectors A and B, and θ is the angle between them.

Therefore, the area of the triangle is equal to:

Area = (|A| x |B| x sin(θ))/2

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In the figure, mGE=99∘, and mHF=41°.

What is m∠GPE?
m∠GPE =
°

Answers

The angle when the secant intersect is as follows:

m ∠GPE = 29 degrees

How to find the angles formed by intersecting secant?

A secant is a line that intersects a circle in exactly two points.

If two secants or chords intersect in the interior of a circle, then the measure of each angle formed is half the sum of the measures of its intercepted arcs.

Therefore,

m ∠GPE = 1 / 2 ( mGE -  mHF)

mGE = 99°

mHF = 41°

m ∠GPE = 1 / 2 (99 - 41)

m ∠GPE = 1 / 2 (58)

Therefore,

m ∠GPE = 29 degrees

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Marsha and Kristen are scuba diving. Marsha is at an elevation of -24 feet, and she is descending at a rate of 12 feet per minute. Kristen is at an elevation of -8 feet and she is descending at a rate of 16 feet each minute. The variable t represents the time in minutes.After how many minutes will Marsha and Kristen be at the same elevation? At what elevation will they be at that time?

Answers

Marsha and Kristen will be at the same elevation of -72 feet after 4 minutes.

How to find their elevation?

To find out after how many minutes Marsha and Kristen will be at the same elevation, we can set their elevation equations equal to each other:

-24 - 12t = -8 - 16t

Then, we can solve for t by adding 8 to both sides and dividing by 4:

t = 4

So, Marsha and Kristen will be at the same elevation after 4 minutes.

To find out what elevation they will be at that time, we can substitute 4 into either one of the elevation equations and solve for the elevation:

-24 - 12(4) = -24 - 48 = -72

So, Marsha and Kristen will be at the same elevation of -72 feet after 4 minutes.

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