Instead use WolframAlpha.com for math questions I would paste the answer but a cretinous fop has "disabled" that feature by javascript -- which is trivial to circumvent but I won't bother with the time.
Answer:
i think the awnser is c . if unattended, leave the horse tire up
Answer:
Lines BC and F represent perpendicular lines
Step-by-step explanation:
we have
<em>Line BC</em>

the slope of the line BC is 
<em>Line F</em>

the slope of the line F is 
we know that
If two lines are perpendicular, then the product of their slopes is equal to -1
so

we have
-----> slope line BC
-----> slope line F
Find the product of their slopes

therefore
Lines BC and F represent perpendicular lines
Find a common denominator which is 12
1*3=3 4*3=12 so 3 3/12
then 5*2=10 6*2=12 so 2 10/12
2 10/12+3 3/12= 5 13/12
13/12= 1 1/12 plus 5= 6 1/12
so your answer would be 6 1/12
V = l * w * h
240 = 20* h
divide both sides by 20
12 = h
height = 12 inches