Cho tam giác ABC có góc A = 60 độ, góc B = 1/2 góc C. Tính

A. $\widehat{B}={70}^o,\widehat{C}={50}^o$

B. $\widehat{B}={30}^o,\widehat{C}={60}^o$

C. $\widehat{B}={40}^o,\widehat{C}={80}^o$

D. $\widehat{B}={80}^o,\widehat{C}={40}^o$