Answer:
3* 10 ^12
Explanation:
(5x10^7)(6x10^4)
Multiply the numbers together
5*6 =30
Add the exponents
10^7 * 10 ^ 4 = 10 ^(7+4) = 10 ^11
30 * 10 ^11
But this is not scientific notation since 30 >10
Move the decimal one place to the left and add 1 to the exponent
3* 10 ^12