Rightmost non-zero digit

$30^{2720} = 3^{2720} \times 10^{2720}$. The rightmost non-zero digit is determined by the unit digit of $3^{2720}$. Since $2720$ is divisible by 4, $3^{2720} \equiv 3^4 \equiv 1 \pmod{10}$. Thus, the rightmost non-zero digit is $1$.