Let \( f \) be a real polynomial of degree \( n \) such that \( f(x)=f'(x)f''(x) \), for all \( x\in\mathbb{R} \). If \( f(0)=0 \), then \( 36\left(f'(2)+f''(2)+\int_{0}^{2}f(x)\,dx\right) \) is equal to:
\( 42 \)
\( 46 \)
\( 56 \)
\( 66 \)