(A) Prove or Disprove That A $6 \times 6$ Checkerboard with Four Squares Removed Can Be Covered with Straight

question 9

Essay

(a) Prove or disprove that a $6 \times 6$ checkerboard with four squares removed can be covered with straight triominoes.
(b) Prove or disprove that an $8 \times 8$ checkerboard with four squares removed can be covered with straight triominoes.