context: ###List of Questions
  (1) Three letters picked without replacement from {a: 1, s: 2, r: 2, q: 9}. Give prob of sequence arr.
  (2) Let b be ((-4)/(-6))/(4/(-6)). Let l be ((b - -1) + 0)*-1. Solve -3*d = 4*x + 2*d + 45, 5*x - 3*d + 10 = l for x.
  (3) Suppose -3*x - 2*x = 0. Suppose 0 = -2*j + 3*v - 8, 2*j - 2*v + 4 = -x*v. What is the units digit of j?
  (4) What is twenty-one eighths of a centimeter in micrometers?
  (5) Calculate -5 divided by -29.
q_1: (1) Three letters picked without replacement from {a: 1, s: 2, r: 2, q: 9}. Give prob of sequence arr.
q_2: (2) Let b be ((-4)/(-6))/(4/(-6)). Let l be ((b - -1) + 0)*-1. Solve -3*d = 4*x + 2*d + 45, 5*x - 3*d + 10 = l for x.
q_3: (3) Suppose -3*x - 2*x = 0. Suppose 0 = -2*j + 3*v - 8, 2*j - 2*v + 4 = -x*v. What is the units digit of j?
q_4: (4) What is twenty-one eighths of a centimeter in micrometers?
q_5: (5) Calculate -5 divided by -29.