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Which of the following statements are TRUE?

There exist $a_1, a_2 \in \mathbb{Z}$ such that $10a_1 + 5a_2 = 5$.

There exist $b_1, b_2 \in \mathbb{Z}$ such that $b_1 + 2b_2 = 1$.

There exist $c_1, c_2 \in \mathbb{Z}$ such that $22c_1 + 33c_2 = 11$.

There exist $d_1, d_2 \in \mathbb{Z}$ such that $77d_1 + 2d_2 = 1$.