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

Given, length, l = 5 cm Now, checking the errors with each options one by one, we getΔl1=5-4.9=0.1 cmΔl2=5-4.805=0.195 cmΔl3=5.25-5=0.25 cmΔl4=5.4-5=0.4 cmError Δl1 is least.Hence, 4.9 cm is most accurate.