This is the last one from me that I need help to solve, please.

6 (a)

Here's the graph https://www.desmos.com/calculator/ej36jt2v3h

(b)  We actually have a trapezoid  here

The height  = 4

One base  =  20

The other  = 180

So...the area (above the x axis )  is

(1/2) (height) (sum of bases)  = 

(1/2) (4) ( 20 + 180)  =

(1/2) (4) ( 200)  =

2 (200)  =

400 units^2

(c)  The function is a velocity function.....the area under the  curve represents the total distance traveled between hour 0  and hour 4