A particle of mass $15\,\text{kg}$ has an initial velocity $\mathbf{v} = \mathbf{i} - 2\mathbf{j}\,\text{m/s}$. It collides with another body and the impact time is $0.1\,\text{s}$, resulting in a velocity $\mathbf{v}_1 = 6\mathbf{i} + 4\mathbf{j} + 5\mathbf{k}\,\text{m/s}$ after impact. The average force of impact on the particle is