Answer:
4
Step-by-step explanation:
Step 1
Let a be directly proportional to m and n^2
a [tex]\alpha[/tex] m(n)²
a = km(n)²
Step 2
Let a be inversely proportional to y^3
a [tex]\alpha[/tex] [tex]\frac{1}{y^{3} }[/tex]
a = [tex]\frac{k}{y^{3} }[/tex]
Step 3
Plug values in the equation to find k
4 = k (9)(4)²/2³
4 = k 144 / 8
4 = 18k
k = 4/18
k = 2/9
Step 4
find a
a = (2/9)(9)(4)²/2³
= 32 / 8
= 4