Explanation:
The sum of something and 2 can only be zero when that something has a value of -2.
The range of the square root function is all non-negative numbers, so it cannot have a value of -2. Thus, the equation cannot have a solution.
You would need to measure the magnetic field first in order to do so
First put both in fraction form
7/12
2/1
use the reciprocal of the second term and multiply
7/12*1/2
7/24
There are 79,200 feet in 15 miles.