Moments

1.a) Ax0.40=0.30x2n
a(0.40)=2n(0.30)
a(0.40)0.40=2n(0.30)/0.40
a=2n(0.75)

1.b)4nx0.25m=0.20xb
4nx(0.25m)/0.20=0.20b/0.20
5n=b
b=5h

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