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.
Find the rate of change, (y2-y1)/(x2-x1), from the data given...
(2.16-1.26)/(12-7)=0.18
(1.26-0.72)/(7-4)=0.18
Since the rate is constant, this is a linear equation of the form y=mx+b. Furthermore, since 0 pencils cost 0, b=0, so the cost of the pencils is simply the number of pencils times 18 cents...
c(p)=0.18p (cost with respect to pencils is 0.18 times the number of pencils)
Answer:
This may be incorrect but $4
Step-by-step explanation:
For a parallelogram, the area is calculated by the equation,
A = bh
where A is area, b is base, and h is height. From this equation, we can solve for the base of the banner by dividing the area by the height.
base of the banner = 127.5 cm² / 4.25 cm
base of the banner = 30 cm
Thus, the measure of the base of the banner is equal to 30 cm.
<span><span>SphereA sphere is the set of all points in space that are a fixed distance from a common point called the center.</span><span>Pyramids<span>A three-dimensional shape with one polygonal base and lateral faces the shape of triangles that meet at a common vertex, called the apex
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