Ten times the sum of a number and 9

In simplified exponential notation, the expression a^2•a^-3•a 1/a 0

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

Determine which postulate or theorem can be used to prove that lmn =nmo