Answer:
See solution below
Explanation:
According to pythagoras theorem
hyp^2 = opp^2 + adj^2
10^2 = 4^2 + b^2
100 = 16 + b^2
b^2 = 100-16
b^2 = 84
b = √84
b ≈ 9
Using SOH CHA TOA identity
sin B = AC/AB
Sin B = 9/10
B = arcsin0.9
B ≈ 64degrees
sinA = BC/AB
Sin A = 4/10
A = arcsin0.4
A ≈ 24degrees