[tex]\begin{gathered} \\ T=816N \\ W=mg \\ 400N=m\times9.8 \\ m=40.8163265306\approx40.8\text{ kg} \end{gathered}[/tex]
The net force.
[tex]\begin{gathered} \text{Net force=}400N-816N \\ \text{Net force=-}416N \end{gathered}[/tex]
This means the cord pulls her upward. Therefore, the magnitude of her acceleration can be calculated as follows
[tex]\begin{gathered} g=\frac{416}{40.8} \\ g=10.1960784314\approx10.2m/s^2 \end{gathered}[/tex]
Note her weight act downward, while the cord pulls her upward direction.
[tex]\text{Magnitude of her acceleration = 10.2 m/s}^2[/tex]
