A 45 kilogram girl is standing on a 136 kilogram plank. The plank, originally at rest, is free to slide on a frozen lake, which is a flat, frictionless surface. The girl begins to walk along the plank at a constant velocity of 1.34 meter per second relative to the plank.
(a) Find what is her velocity relative to the surface of ice?
m/s
(b) Determine the velocity of the plank relative to the surface of ice?
m/s