Comprehension: \( \quad: \) Consider the real valued function \( f: R \rightarrow R \) defined a...

Comprehension: \( \quad: \) Consider the real valued function \( f: R \rightarrow R \) defined as \( f(x)=x^{2} e^{-x} \)
Number of solutions of the equation \( 4 x^{2} e^{-x}-1=0 \) is
(a) 0
(b) 1
(c) 2