(1 point) Let P, be the vector space of all polynomials of degree 2 or less, and let H be the subspace spanned by 2- (10z + 15z), 7z+ 4z-2 and 1-(5z+7z). a. The dimension of the subspace His b. Is (2-(10z2 + 15z), 72+42-2,1- (5z+7)) a basis for P,7 choose c. A basis for the subspace His { (where you can enter xx in place of ) Be sure you can explain and justify your answer. Enter a polynomial or a comma separated list of polynomials