What does pressure mean

Acatapult is tested by roman legionnaires. they tabulate the results in a papyrus and 2000 years later the archaeological team reads (distances translated into modern units): range = 0.4 km; angle of launch = π/5 rad; landing height = launch height. what is the initial velocity of launch of the boulders if air resistance is negligible?

According to social exchange theory, altruistic behaviors benefit the individual who performs them. t/f

Which configuration would produce an electric current? a) rotate a coil of copper wire between two magnets. b) connect a wire between a copper and zinc strip sitting in a beaker of water. c) connect a wire to the (+) positive end of a battery and the other end to a light bulb. d) connect a wire to the negative end of a battery and the other end to a light bulb.