QUESTION 4 Show that ū€ span {(1,2,-1,0),(1,1,0,1),(0,0, — 1,1)} where ū=(2,5, -5,1) by finding scalars k,/ and m such that ū=k(1,2,-1,0) + /(1,1,0,1)+m(0,0,-1,1). k= 1 = m=