Aparticle moves along the x axis. its position is given by the equation with x in meters and t in seconds. determine
(a) its position at the instant it changes direction and
(b) its velocity when it returns to the position it had at t = 0.

A0.750 kg aluminum pan is removed from the stove and plunged into a sink filled with 10.0 kg of water at 293 k. the water temperature quickly rises to 297 k. what was the initial temperature of the aluminum pan? the specific heat of aluminum is ca = 900 j/(kgk) and water is cw = 4190 j/(kgk)