Please help with A and B

A 0.43 kg gold bar is released from rest 0.46 m above the surface of a pond, which is 1.78 m deep. When the bar reaches the water and falls in the water, a constant upward force of 0.78 N is exerted on it by water resistance. Let y = 0 be at the bottom of the pond. - gold bar surface of pond 0.46 m y = 178 m- 1.78 m water in po of 4 = 0 A. (4) What is the speed of the gold bar when it reaches the surface of the pond? Neglect air resistance. B. (16) What is the speed of the gold bar when the depth of the bar below the water's surface is 1.3 m