In fig shows a block and tackle system of pulleys used to lift a load .
(a) How many strands of tackle are supporting the load ?
(b) Draw arrows to represent tension T in each strand.
(c) What is the mechanical advantage of the system ?
(d) When load is pulled up by a distance 1 m, how far does the effort end move ?
(e) How much effort is needed to lift a load of 100 N ?