3*5 ≡ 15 ≡ 3 (mod 12)
3*7 ≡ 21 ≡ 9 (mod 12)
3*9 ≡ 27 ≡ 3 (mod 12)
5*7 ≡ 35 ≡ 11 (mod 12)
5*9 ≡ 45 ≡ 9 (mod 12)
7*9 ≡ 63 ≡ 3 (mod 12)
Your table should look like the attached.
It's unclear what you're supposed to evaluate for part (b)...
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