F - Irrational, -13.8
Because the negative sign is not inside of the radical, we can tell that the number is being multiplied by the negative. Thus, do the radical equation first, get the answer 13.8202... and multiply by -1 to get the answer. Also, it is irrational because it is not a perfect square.
The answer for the question is 4
I think it would be 54 degrees
To solve an equation with a rational (fraction) coefficient you need to multiply both sides of the equation by the reciprocal (invert the fraction - flip it).

The reciprocal of 1/6 is 6/1 or 6

The product of reciprocals equals 1
1x = 24
x = 24
Mr. Toshio had 32 rulers.
32-11 = 21 rulers.
21+4 = 25 rulers.
and
25-7 = 18 rulers