Answer:
(d)
Step-by-step explanation:
Given

Required
The intercepts
The x intercepts are where the graph crosses x axis.
From the attached plot, they are:
and 
These represent the start and end of the ball that is launched.
Hence, (d) is true
The answer is y=3(x-1)^2+6
Gross pay is before taxes are taken out...
11.25(40) = 450 <== gross weekly pay
Given
we are given a function

over the interval [0,5].
Required
we need to find formula for Riemann sum and calculate area under the curve over [0,5].
Explanation
If we divide interval [a,b] into n equal intervals, then each subinterval has width

and the endpoints are given by

For k=0 and k=n, we get

Each rectangle has width and height as

we sum the areas of all rectangles then take the limit n tends to infinity to get area under the curve:

Here




Now Area=

So the required area is 66.6 sq units.