The block moves a distance l up the incline. the block does not stop after moving this distance but continues to move with constant speed. what is the total work wtot done on the block by all forces? (include only the work done after the block has started moving, not the work needed to start the block moving from rest.)

Total work done  = Wtot = 0

Explanation:

The work energy theorem is used to find the total work done of the block =

Wtot = Kf− Ki

The Kinetic energy change of the block from its start until it has pulled a distance.  

Here kinetic energy is considered  

If the speed of the block not change , its kinetic energy also cannot change

Kf − Ki = 0

Wtot = 0

i think it'll be 7,000