We know that power is given by:
[tex]\begin{gathered} P=\frac{W}{t} \\ \text{ where } \\ W\text{ is the work } \\ t\text{ is the time} \end{gathered}[/tex]we also know that the work is given by:
[tex]W=Fd[/tex]where F is the force and d is the distance.
From the statement we know that only 25% of the force is directed forward, this means that the force that does work is:
[tex]\begin{gathered} F=0.25(201) \\ F=50.25 \end{gathered}[/tex]Now that we know the force we can find the work done by it if we multiply it by the 6.3 m the man pushes the lawn mower:
[tex]\begin{gathered} W=(50.25)(6.3) \\ W=316.575 \end{gathered}[/tex]Finally we plug this in the power formula and the time of 14 s given, then we have:
[tex]\begin{gathered} P=\frac{316.575}{14} \\ P=22.61 \end{gathered}[/tex]Therefore, the power expend by the man is 22.61 W (rounded to two decimal places)