(1 point) How many pivot variables does each augmented matrix have? 1 -2 -5 a. Choose 0 0 0 0 0 0 1 b. Choose 0 0 c. Choose d. Choose 1 0 0 1 -7 0 0 0 0 -2 3 0 0 0 0 8 -7 00 -4 0 1 0 10 0 2 7 3 0 1 0 1 0 80 6x - 3y - 3z = -30 -x - 2y + 4z x - 5y + 2z = 35 = 30 How many solutions are there to this system? A. None B. Exactly 1 C. Exactly 2 D. Exactly 3 E. Infinitely many F. None of the above If there is one solution, give its coordinates in the answer spaces below. If there are infinitely many solutions, enter the parameter t in the answer blank for z., enter a formula for y in terms of t in the answer blank for y and enter a formula for x in terms of t in the answer blank for x. If there are no solutions, leave the answer blanks for x, y and z empty. X = y = 7. = (1 point) Consider a linear system whose augmented matrix is 1 1 5 1 2 -3 4 12 k For what value of k will the system have no solutions? k= -1 -3 -19