which of these are correct
(2.9 x 10^8) (1.3 x 10^7) = 3.77x 10^15
(4.6 x 10^5) (2.1 x 10^4) = 2.5 x 10
(9.9 x 10^7) (5.8 x 10^6) = 5.72 x 10^13
(8.8 x 10^8) (4.2 x 10^7) = 13 x 10^15
The correct equation is:
(2.9 x 10^8) (1.3 x 10^7) = 3.77 x 10^15