Answer:
Following are the solution to the given points:
Step-by-step explanation:
p= amount at any time
then 


at time 

y= amount at any times
For point a:
For point b:
For point c:

Answer:
4+x
Step-by-step explanation:

Answer:
-3
Step-by-step explanation:
The rate of change is equal to the slope. In this slope intercept form (y=mx+b) m is the slope. Therefore m=-3 and that is the rate of change.