Answer:
A is correct don't you know
There are 9 seniors.
Although there are several ways of solving this problem, I just did what was easiest for me in my head. I divided 36 by 4, which gave me 9.
Step-by-step explanation:

Answer: 6
Step-by-step explanation:
the area of the base is the triangle base
the area of a triangle is bh/2
that looks like a perpendicular sign in the top left so b = 3 and h = 4
so area = 3*4/2 = 6
Add the amount of students together (21+24=45)
Divide by three to see how many will be in each group. (45/3 = 15)
15 in each group!