I have attached an image of how I solved this problem:
The answer is B
Solution:
Find perimeter (L+B+L+B)
600+300+600+300= 1,800
1,800/3= 600
600x500= 300,000
1.98x10^9. move the decimal until you have one number in front of it. then keep the numbers that are not 0 after it. then count how many places you moved the decimal point and that's your power.
1. 4.3904x
That's number one... Sorry, I can't do ten of those problems.... Gtg.... Hope I helped!!!!! Good luck!!! :)