a
\(x=4 \mathrm{~m}, \mathrm{~V}=2 \mathrm{~m} / \mathrm{s}, \mathrm{a}=16 \mathrm{~m} / \mathrm{s}^2\)

\(|\mathrm{a}|=\omega^2 \mathrm{x}\)

\(\Rightarrow 16=\omega^2(4)\)

\(\omega=2 \mathrm{rad} / \mathrm{s}\)

\(\mathrm{v}=\omega \sqrt{\mathrm{A}^2-\mathrm{x}^2}\)

\(A=\sqrt{\frac{\mathrm{v}^2}{\omega^2}+\mathrm{x}^2} \Rightarrow \mathrm{A}=\sqrt{\frac{4}{4}+16}\)

\(A=\sqrt{17} \mathrm{~m}\)