The kinetic energy is given by:
\[ KE = \frac{P^2}{2m}, \quad \text{where } P \propto \sqrt{m}. \]
For masses \(m_A = 400 \, \text{g}, \, m_B = 1.2 \, \text{kg}, \, m_C = 1.6 \, \text{kg}\):
\[ P_A : P_B : P_C = \sqrt{400} : \sqrt{1200} : \sqrt{1600}. \]
Simplify:
\[ P_A : P_B : P_C = 1 : \sqrt{3} : 2. \]
Final Answer: 1 : \(\sqrt{3}\) : 2.
Let $ f: \mathbb{R} \to \mathbb{R} $ be a twice differentiable function such that $$ f''(x)\sin\left(\frac{x}{2}\right) + f'(2x - 2y) = (\cos x)\sin(y + 2x) + f(2x - 2y) $$ for all $ x, y \in \mathbb{R} $. If $ f(0) = 1 $, then the value of $ 24f^{(4)}\left(\frac{5\pi}{3}\right) $ is: