Given Data:
L = 6m
W1 = 8kN
W2 = 8kN
Solution:
Maximum S.F = 8 + 8 = +16kN

Maximum B.M = -WL
Moment at support A, MA = 0kN.m
Moment at support B, MB = -(8 x 3) = -24kN.m
Moment at support C, MC = -[(8 x 3) + (8 x 6)] = -72kN.m

Result:
Max S.F = +16kN
Max B.M
MA = 0kN.m
MB = -24kN.m
MC = -72kN.m