Answer:
<em>t = 1.51</em>
Step-by-step explanation:
<u>Exponential Model</u>
The exponential model is often used to simulate the behavior of a magnitude that either grow or decay in proportion to the existing amount of that magnitude.
The model can be expressed as

In this case, Mo is the initial mass of the radioactive substance and k is a constant which value is positive if the mass is growing or negative if the mass is decaying.
The value of k is not precisely given in the question, we are assuming 
The model is now

We are required to compute the time it takes the mass to reach one-half of its initial value:

Simplifying

Taking logarithms

Solving for t

Answer:
C is the correct one
Step-by-step explanation:
I’ve done it before
Answer:
.90(85.00) would give the same result
Step-by-step explanation:
Rhonda is using the total cost of the item ($85.00) multiplied by the discount (10%) to find the total discount: 85 x 0.10 = 8.50. Once Rhonda subtracts the discount ($8.50) from the total: $85 - $8.50 = $76.50. The other way to look at the problem, is that Rhonda is only paying for 90% of the total cost of the items, instead of 100% since she is receiving the 10% discount. So, she would get the same final total by multiplying the cost of the items ($85.00) by 90%, or 0.90.
k = 0 means the parabola has one zero, because the vertex is just on the x-axis. k > 0 means the parabola has none zeros, because the vertex will be above the x-axis and it will not intersect the x - axis.
Answer:
Step-by-step explanation:
1.
Area of shaded region = Area of external rectangle - Area of internal rectangle

2.
Let the width of the rectangle be x inches.
Therefore, length of the rectangle = (x + 3) inches
A.
Area of rectangle
B.
Width of rectangle = 4 inches
Length of rectangle = 4 + 3 = 7 inches
Area of rectangle = 7*4 = 28 square inches.