A 3.0kg cart is initially at rest on a frictionless track. A constant horizontal force of 6.0N to the east acts on the cart for 0.20s, after which the net horizontal force is zero for the next 1.0s. Finally, a 6.0N force to the west acts for 0.10s. What is the magnitude and direction of the cart’s velocity at t=1.30s?
a) 0.60m/s east
b) 0.20m/s east
c) 0.20m/s west
d) 0.40m/s east