How do I figure this out?

Question

(3.7 x 10¹⁴) x (9.1 x 10^-13) = ? The answer is 3.367 x 10², but how?

Answer 1

(3.7 x 10¹⁴) x (9.1 x 10^-13)

     = (3.7 × 9.1) × (10¹⁴ × 10^-13)   [Applied commutative law and regrouped]

     = (33.67) × (10^14-13)                [Exponent Property: a^b×a^c = a^b+c]

     = (3.367 × 10) × 10

     = 3.367 × 10¹⁺¹

     = 3.367 × 10²