Is this correct? if not, let me know the correct answer.

Terri makes a quilt using three sizes of fabric squares the side lenght of each fabric square is the square root of the area

Find the volume of the described solid.the solid lies between planes perpendicular to the x-axis at x = 0 and x=7. the cross sectionsperpendicular to the x-axis between these planes are squares whose bases run from the parabolay=-31x to the parabola y = 30/x.a) 441b) 147c) 864d) 882

In the polynomial below, what number should replace the question mark to produce a difference of squares? x2 + ? x - 36