What is the work done by a coolie walking on a horizontal platform with a load on his head?

The work done on an object does not depend upon the

$A$ force of $7\, N$ acts on an object. The displacement is $8\, m$ in the direction of the force. What is the work done in this case (in $, J$)?

$A$ man weighing $70 \,kg$ carries a weight of $10 \,kg$ to the top of a tower $100 \,m$ high. Calculate the work done.

The work done in lifting a box onto a platform does not depend upon how fast it is lifted up. Explain your answer giving proper reasoning.

Calculate the amount of work done in moving a $50 \, kg$ mass through a distance of $10 \, m$ by applying a force of $100 \, N$. (in $, J$)