Answer:
(a)

(b)

(c)

Step-by-step explanation:
(a)
Simply evaluate (a+h) in the function:

(b)
Evaluate (a) in the function:

Using the previous answers lets calculate f(a+h)-f(a)

(c) To find the rate of change of f(a+1) when a=7 we need to calculate its derivate at that point:

Answer:
Step-by-step explanation:
8z (3x^2 +y)
The perimeter will be the perimeter of the real thing divided by 1.2 .
The area will be the area of the real thing divided by (1.2)² .