We are given the area, so we can find the length
A = L*W
2.76 * 10 ^12 = L * 4.6 * 10 ^5
Divide each side by 4.6 * 10 ^5
2.76 * 10 ^ 12 / 4.6 * 10 ^5 = L
6 * 10 ^ 6 = L
Now the perimeter is found by
P = 2 ( L+W)
P = 2 ( 6*10 ^6 + 4.6* 10 ^5)
We need the exponents the same to add)
P =2 ( 60*10^5 + 4.6 * 10^5)
P =2 ( 64.6 *10^5)
= 129.2 * 10 ^5
Moving the decimal 2 places
1.29 * 10^7 cm