Answer:
32/24
Step-by-step explanation:
opposite/ adjacent
If 40% of students prefer keyboarding, 40/100*40=16 students like it best. If the remaining students prefer English, then 40-16=24 students like English best. Since 24 is more than 16, most students prefer English.
These lines are perpendicular because y = -6 is a horizontal line with a slope of 0 and x = 6 is a vertical line with an undefined slope
The answer is

In the choices; the coefficients 21, 32 and 10 are not perfect squares.