Perpendicular to the plane
SF = 0
N - mg cos 37.1 = 0
N = mg cos 37.1
f = mN = 0.2 X 20 X 9.8 X 0.8 = 31.36 N

Along the plane
SF = ma
200 - mg sin 37.1 - f = ma
200 - (20)(9.8)(0.6) - 31.36 = 20a
a = 51.04/20 = 2.55 m/s2

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