I don’t know the answer to all but hopefully this will help u out a little bit:
0 hours would be 0 dollars of course
0.5 hours would be $2.50
1 hour would be $5
2 hours would be $10
The boundaries:
x = 0, y = 8; y = 0, √x³ = = 8, x = 4


= π ( 64 x - 16 * 2 *√x^5 + x^4 / 4 ) =
= π ( 320 - 1024/5 + 64 ) =
179.2 π
Answer:
a) For Bella, x has to be a positive even values
For Tito, x has to be a negative even values
b) For Bella, x = 4
For Tito, x = -4
You can just set y=0 and solve for x. when you do this you should get 1/2x^2=4
x^2=8
x=2.8 and -2.8 ( you have both a positive number and negative number since (-2.8)^2=(2.8)^2 =8
I hope this helps