"in the figure below, sin a = 0.7.

what is the length of ac ?

a

14.7

b

21.7

c

30

d

32"

We Know, Sin ∅ = P/H

Sin A = BC/AC

0.7 = 21 / AC

AC = 21/0.7

AC = 30

So, your answer is AC = 30

a complex number is a number that can be expressed in the form a + bi, where a and b are real numbers, and i is a solution of the equation x2 = −1. because no real number satisfies this equation, i is called an imaginary number. has no real solution, since the square of a real number cannot be negative.