Answer:
a. 
b. 
Step-by-step explanation:
First, we need tot find a general expression for the amount of caffeine remaining in the body after certain time. As the problem states that every hour x percent of caffeine leaves the body, we must substract that percentage from the initial quantity of caffeine, by each hour passing. That expression would be:

Then, to find the amount of caffeine metabolized per hour, we need to differentiate the previous equation. Following the differentiation rules we get:

The rate is negative as it represents the amount of caffeine leaving the body at certain time.
<h3>
Answer: 8</h3>
Reason:
Replace p with 2 and evaluate.

Think of a cube that is 2 units along each side. It's volume is 2*2*2 = 8 cubic units. Repeated multiplication can be shortened to using exponents.
Another example: 
Answer:
6500
Step-by-step explanation:
Answer:
13.86 ft
Step-by-step explanation:
This can be represented by a right angled triangle with a hypotenuse of 16 feet and an angle of 60° between the hypotenuse side and the adjacent side.
The height of the pole is the side opposite to the angle 60°.
The trigonometric function states that for a right angled triangle:
sinθ = opposite / hypotenuse, cosθ = adjacent / hypotenuse, tanθ = opposite/ adjacent
To find the height of the flagpole, we use:
sin(60) = height / 16
height = 16 * sin(60)
height = 13.86 ft
The person with the incorrect reasoning for the height of the flagpole is Charlie when he should have utilized the sin function. Because he incorrectly selected the function.