A particle of mass 2 kg has acceleration (2i+j)(2\mathbf{i}+\mathbf{j})(2i+j) m s−2^{-2}−2. Three forces (3i−4j)(3\mathbf{i}-4\mathbf{j})(3i−4j) N, (ki+2j)(k\mathbf{i}+2\mathbf{j})(ki+2j) N and (−5i+4j)(-5\mathbf{i}+4\mathbf{j})(−5i+4j) N act on it.
Find kkk.
Verify that the j\mathbf{j}j-components satisfy Newton's second law.