Nellie Newton does work on a box by pushing it with a constant force of 100 N over a distance of 4 m. (a) If Nellie pushes the object with twice the force over the same distance, how much work does she do? (b) If she pushes with the original force (100 N) over 8 m how much work does she do?

Ahot-air balloon takes off from the ground traveling vertically with a constant upward acceleration of magnitude g/4. after time interval δt, a crew member releases a ballast sandbag from the basket attached to the balloon. how many seconds does it take the sandbag to reach the ground? (express your answer in terms of δt)