2. a baseball player shoots a ball at an angle such that the horizontal and the vertical
components of velocity are each equal in magnitude to 7.0 m/s. the angle to the
horizontal at which the ball is shot is
a. 60°
b. 45°
d. 90°
c. 30°

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.