Use the pumping lemma to show that each of the following languages is not regular.

1) L = {0ⁱ1^j |j is a multiple of i}

2) L = {x {0, 1}^* |n₀ (x) < 2n₁ (x)}

3) L = {x {0, 1}^* | no prefix of x has more 1s than 0s}