We actually need to find the unit place digit of(171)×(1317)×(1491)×(2)197. The unit place digit of 17 = 7, The unit place digit of (1317)=34×4×31=3, The unit place digit of (149) = 9, The unit place digit of (2)196=249×4×2=2, So, the unit place digit of 171×1317×1491×2197=7×3×9×2=378. So, the unit place digit is 8.