Answer:
a) $109
b) 
c) 
Step-by-step explanation:
a) The marginal cost, or the cost per additional unit, is given by the derivate of the cost function:

b) Profit is given by Revenue minus Cost:

c) The marginal profit for 8 units, is given by the difference in profit for 9 units and 8 units:

Check the picture below.
using a second for it, since it's a horizontal line, then say hmmm we'll use the y-intercept, or (0, 1), so the equation of a line that passes through (2,1) and (0,1)
Step-by-step explanation:
C= 72..............
C3=216
C=216
3
C = 72
Thanks
So you wanna find the area of each surface:
For the large square surface in the top you do 12*15=180 and there are two large squares faces so you multiply 180 by 2 which equals 360 then you find the small rectangle faces: 5*15=75 and multiply by 2 Bc there are 2 faces like that so it would be 75*2=150 then for the last faces you do 12*5= 60 *2= 120 at the end I add all of the faces up, 360+150+120=630