Question

The metre, symbol m, is the SI unit of length. It is defined by taking the
fixed numerical value of the speed of light in vacuum c to be 299792458
when expressed in the unit m s', where the second is defined in terms of
the caesium frequency AVCS.
means ​

Answer 1

Answer:

What is a metre -

https://yo utu.be/2Rd7kLv-mJw

What is a second -

https://yo utu.be/dcVQ8Kd4DFU

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