1) Given that 

In a triangle sum of the angles is 180

A + B + C = 180

A + 18 + 37 = 180

A + 55 = 180

A = 180 - 55

Apply sine rule

5.136 = c

Therefore c = 5.14

Answer is option ( b )

2) Given that

Apply cosine rule

a = 5.244

Therefore  a = 5.25

Answer is option ( d )