The mean length of an object is 5 cm. Which of the following measurements is most accurate?

Given length l = 5 cmNow, checking the errors with each options one by one, we getΔl1 = 5−4.9 = 0.1cmΔl2 = 5−4.805 = 0.195cmΔl3 = 5.25−5 = 0.25cmΔl4 = 5.4−5 = 0.4 cmError Δl1 is leastHence 4.9 cm is most precise.