10) (Honors) To give a \( 19-\mathrm{kg} \) childl a ride, two teenagers pull on a 3.7 kg sled with ropes, as indicated in the figure. Both teenagers pull with a force of 55 N at an an angle of 35 degrees relative to the forward direction, which is the direction of motion. In addition, the snow exerts a retarding force on the sled that points opposite to the direction of motion, and has a magnitude of 57 N . Find the acceleration of the sled with the child.
\[
\begin{array}{c}
\text { nof the sled with the child. } \\
\cos (35)
\end{array}
\]
