(a) Constant velocity implies zero acceleration, so the “uphill” force must equal (in magnitude) the “downhill” force: T=mgsinθ. Thus, with m=50kg and θ=8.0o , the tension in the rope equals 68N.
(b) With an uphill acceleration of 0.10m/s2, Newton’s second law (applied to the x axis) yields
T−mgsinθ=ma⇒T−(50kg)(9.8m/s2)sin8.0o=(50kg)(0.10m/s2)
which leads to T=73N.