There are atomic clocks capable of measuring time with an accuracy of 1 part in $10^{11}$. If two such clocks are operated with precision , then after running for $5000\;year$ these will record. - Clay6.com, a Free resource for your JEE, AIPMT and Board Exam preparation

There are atomic clocks capable of measuring time with an accuracy of 1 part in $10^{11}$. If two such clocks are operated with precision , then after running for $5000\;year$ these will record.

$\begin{array}{1 1} \text{a difference of 1.6s} \\ \text{a difference of 1 day} \\ \text{a difference of} \;10^{11} \;S \\ \text{a difference of 1 year } \end{array} $