How will changing either of the masses affect the gravitational forces between them

What tightening torque should be used for a hexagonal head screw (not split-bolt) on a 250 kcmil conductor?

Aclarinetist, setting out for a performance, grabs his 3.350 kg clarinet case (including the clarinet) from the top of the piano and carries it through the air with an upward force of 24.65 n. find the case's vertical acceleration. indicate an upward acceleration as positive and a downward one as negative.

What’s #16 asking me and how do i solve it?