Help me please I don't know how to do this

What is the distance between (–2 1/2,-3) and (1, –3)?

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

Wrote and expression for the difference of p and 4