Question

The formula s= sqrt SA/6

Answer 1

For this case we have the following equation:
 s = root (S.A / 6)
 Substituting values we have:
 For S.A = 180:
 s = root (180/6)
 s = root (30)
 For S.A = 120:
 s = root (120/6)
 s = root (20)
 s = root (4 * 5)
 s = 2 * root (5)
 Subtracting both values we have:
 root (30) - 2 * root (5)
 Answer:
 root (30) - 2 * root (5)
 option 2