Answer:
3.9 X 10^11
Explanation:
(3 x 10^8) ( 1.3 x 10^3)
Step 1: The bases with exponents are the same so put those together!
(3 x 1.3) (10^8 x 10^3)
Step 2: Since both bases are together ADD them, the rest you can continue as is
(3 x 1.3) (10^8+3)
Step 3: Solve!
3.9 x 10^11