Answer:
Step-by-step explanation:
(1) From the given figure, it is given that , and , thus using the trigonomtery, we have
⇒
⇒
⇒
⇒
therefore, the measure of the angle B is 30°.
Hence, option A is correct.
(2) From the given figure, using the trigonometry, we have
⇒
⇒
⇒
Thus, option C is correct.