Question

One second is equal to

• A. 1650763.73 time periods of $Kr$ clock
• B. 652189.63 time periods of $Kr$ clock
• C. 1650763.73 time periods of $Cs$ clock
• D. 9192631770 time periods of $Cs$ clock

Answer 1

Answer: (D)

9192631770 time periods of $Cs$ clock

Answer 2

It is by standard definition.