The gain in kinetic energy (KE) of the box is given by:

\(\text{Gain in KE} = \frac{1}{2} \times 25 \times 3^2 = 112.5 \text{ J}\)

The work done (WD) by the pulling force is:

\(\text{WD by pulling force} = 220 \times 15 \times \cos \alpha\)

According to the work-energy principle, the work done by the pulling force is equal to the gain in kinetic energy plus the work done against resistance:

\(220 \times 15 \times \cos \alpha = 112.5 + 3000\)

Solving for \(\cos \alpha\):

\(3300 \times \cos \alpha = 3112.5\)

\(\cos \alpha = \frac{3112.5}{3300}\)

\(\cos \alpha \approx 0.943\)

\(\alpha = \cos^{-1}(0.943) \approx 19.4^\circ\)