for 2)
Apply newton II horizontally (to the right)
12000 - xcos25 - xcos25 = 0 ----(x=tension in each of other rope)
xcos25=6000
x = 6620N
b) Power = Fv = 12000 x 1.8 = 21600W but this is only 25% of power supplied,
so power supplied = 21600 / 0.25 = 86400W