These are quite easy if you know congruency...
7103 is divided by 5
From Fermat Little Theorem,

3232power 32 is divided by 7

So leaves remainder 4 when divided by 7..
3232 is divided by 3

22225555 + 55552222 is divided by 7


So, 22225555 + 55552222 leaves remainder 0 when divided by 7