Answer: 625
Step-by-step explanation:
We have the numbers 5x10^8 and 8x10^5
the relation between them can be obtained by:
(5x10^8)/(8x10^5)
now, we can solve this as:
(5/8)*(10^8/10^5) = (5/8)x10^(8-5) = (5/8)x10^3 = 0.625x10^3 = 625
where we used that:
(a^b)/(a^c) = a^(b-c)
then the correct option is the second one.