What mass of lead has the same volume as 1600kg of gasoline?

Newton's law of universal gravitation states that the force f between two masses, m1 and m2, is given below, where g is a constant and d is the distance between the masses. find an equation that gives an instantaneous rate of change of f with respect to d. (assume m1 and m2 represent moving points.)

Aplane flying horizontally at an altitude of 1 mile and a speed of of 500mih passes directly over a radar station. find the rate at which the distance from the plane to the station is increasing when it is 2mi away from the station.

Estimate the change in the gibbs energy and molar gibbs energy of 1.0dm3 of octane when the pressure acting on it is increased from 1.0 atm to 100 atm. the mass density of octane is 0.703 g cm−3