The answer is b with the angles
Finding the upper and lower bounds for a definite integral without an equation is pretty hard because how can we find the upper and lower bounds of definite integral if there is no equation given. But I will teach you how to find the lower and upper bounds of a definite integral, when the equation is like this
So, i integrate this,

I know I have a minimum at x=3 because;
f(t )= t^2 − 6t + 11
f′(t) = 2
t−6 = 0
2(t−3) = 0
t = 3
f(5) = 4
f(1) = −4
Answer:
It is a Cuboid
Area of the base = 12x9
Area of the top = 12x9
Area of the right lateral faces = 9x7
Area of the left lateral faces = 9x7
Area of the front face = 12x7
Area of the rear face = 12x7
Total surface area is the sum of above (please do it yourself)
The volume = base surface Area x height
= 12x9x7 = 756
Be reminded to put in the right unit for Area and volumn