Let $H(x)=$SHA$-256(x)mod10$

Is $H(x)$ a collision resistant hash function? If yes, describe why. If no$,$ how would you find a collision?

Let $x=x_1||x_2||dots||x_n$ where each piece $x_i$ is $64$ bits long.

Let $G(x)=x_1^{H(x_1)}||x_2^{H(x_2)}||dots||x_n^{H(x_n)},$ where $x_i^{H(x_i)}$ is regular exponentiation, and $H$ is as defined above.

Is $G(x)$ collision resistant? If yes, describe why. If no$,$ find a collision.

$($Hint: What if $x$ is only a single piece?$)$