Why would a positive current flow from the positive end of a wire towards its negative end?

An ideal gas is held in a container at constant volume. initially, its temperature is 5 degrees c and its pressure is 1.2 atm. what is its pressure when its temperature is 43 degrees c? answer in units of atm

What would be the radius of the earth if it had its actual mass but had the density of nuclei? express your answer to two significant figures and include the appropriate units.

If you held a stone over the mouth of a well and then let it go , what would happen to the stone? explain your answer.