How to find missing angles parallel

Given the sequence 7, 14, 28, 56, which expression shown would give the tenth term? a. 7^10 b. 7·2^10 c. 7·2^9

A.s.a.! this is a similarity in right triangles. next (solve for x)a.) 12b.) 5c.) 12.5d.) [tex] 6\sqrt{3} [/tex]

Answer! if you don’t mind, can you explain