I dont know what is the answer

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

Find the domain of the following expression: 1/(√x)-2

Ntriangle abc, m∠a = 35° and m∠b = 40°, and a=9. which equation should you solve to find b?