Please help me find the solution to these practices problems. Please show work and number the questions.

7: Let S =$ 4 3 - 3 and W = Span (S). I: Find a basis for W. Il: What is the dimension of W , dimW ? 8: Determine whether the set of polynomials S = {4x - x2 ,5+ x3,5+3x, -3x2 + 2x3} is a basis for P3 , the set of all polynomials of degree 3 or less. 9: Find the coordinates of v = 2 in R with respect to the basis