The work-energy principle states that the work done is equal to the change in kinetic energy plus the work done against resistance.

The change in kinetic energy (KE) is given by:

\(\text{KE gain} = \frac{1}{2} \times 80 \times (5.5^2 - 4^2) = 570 \text{ J}\)

The work done against resistance is:

\(\text{WD against Res} = 60P\)

According to the work-energy equation:

\(\frac{1}{2} \times 80 \times (5.5^2 - 4^2) + 60P = 1200\)

Substituting the KE gain:

\(570 + 60P = 1200\)

Solving for \(P\):

\(60P = 1200 - 570\)

\(60P = 630\)

\(P = \frac{630}{60} = 10.5\)