Answer: 43.1 degrees (choice B)
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Work Shown:
Use the law of sines
sin(A)/a = sin(C)/c
sin(A)/20 = sin(82)/29
sin(A) = 20*sin(82)/29
sin(A) = 0.68294349
A = arcsin(0.68294349)
A = 43.074088
A = 43.1 degrees