Find a basis for each of these subspaces of r4 :
a) all vectors whose components are equal.
b) all vectors whose components adds to zero.
c) all vectors that are perpendicular to (1,1,0,0) and(1,0,1,1)
d) the column space(in r2) and nullspace (in r5) of u= [ (1 0 1 01); (0 1 0 1 0)]

Afactory buys 10% of its components from suppliers b and the rest from supplier c. it is known that 6% of the components it buys are faulty. of the components brought from suppliers a,9% are faulty and of the components bought from suppliers b, 3% are faulty. find the percentage of components bought from supplier c that are faulty.