Answer:
B. 3.6 x 10^3
Explanation:
(1.2 x 10^-2) x (3 x 10^5)
When we multiply terms with powers , we multiply the factors out front and add the exponents
a * 10^b * c* 10^d = ac * 10^(b+d)
(1.2 x 10^-2) x (3 x 10^5) = (1.2* 3) * 10^(-2+5)
= 3.6 * 10 ^3