its wrong can u redo it

Step 1: Use the kinematic equation for maximum height where final velocity $v_f = 0$ m/s at the top.

$v_f^2 = v_i^2 + 2 a s$

Step 2: Substitute values with units: $v_i = 20$ m/s, $a = -g = -10$ m/s², $s = h$ (maximum height).

$0^2 = (20 m/s)^2 + 2 (-10 m/s^2) h$

Step 3: Simplify.

$0 = 400 m^2/s^2 - 20 m/s^2 \cdot h$

Step 4: Solve for $h$.

$20 m/s^2 \cdot h = 400 m^2/s^2$

$h = \frac{400 m^2/s^2}{20 m/s^2} = 20 \text{ m}$

Final answer: $\boxed{20 m}$