1. We need to find the units digit of $4^{7022}$. 2. The units digit of powers of 4 cycle every 2: $4^1=4$, $4^2=16$ (units digit 6), $4^3=64$ (units digit 4), $4^4=256$ (units digit 6), and so on. 3. Since the cycle length is 2, find $7022 \bmod 2$: $7022 \div 2 = 3511$ remainder 0. 4. When the exponent is even, the units digit is 6. So, units digit of $4^{7022}$ is 6. --- 1. Find the units digit of $2^{6543}$. 2. Units digits of powers of 2 cycle every 4: 2, 4, 8, 6. 3. Find $6543 \bmod 4$: $6543 \div 4 = 1635$ remainder 3. 4. The units digit corresponds to the 3rd number in the cycle, which is 8. 5. So, units digit of $2^{6543}$ is 8. --- 1. Find the units digit of $3^{11707}$. 2. Units digits of powers of 3 cycle every 4: 3, 9, 7, 1. 3. Find $11707 \bmod 4$: $11707 \div 4 = 2926$ remainder 3. 4. The units digit corresponds to the 3rd number in the cycle, which is 7. 5. So, units digit of $3^{11707}$ is 7. --- 1. Find the units digit of $8^{8985}$. 2. Units digits of powers of 8 cycle every 4: 8, 4, 2, 6. 3. Find $8985 \bmod 4$: $8985 \div 4 = 2246$ remainder 1. 4. The units digit corresponds to the 1st number in the cycle, which is 8. 5. So, units digit of $8^{8985}$ is 8.