Which of the following pairs is incorrect?

What is the accuracy of an atomic clock?

Explain the concepts of accuracy and precision in measurement with an example.

What is mass? Write the effect of external factors on mass.

When the planet Jupiter is at a distance of $824.7$ million kilometers from the Earth,its angular diameter is measured to be $35.72''$ of arc. Calculate the diameter of Jupiter.

$A$ $LASER$ is a source of very intense,monochromatic,and unidirectional beam of light. These properties of a laser light can be exploited to measure long distances. The distance of the Moon from the Earth has been already determined very precisely using a laser as a source of light. $A$ laser light beamed at the Moon takes $2.56 \; s$ to return after reflection at the Moon's surface. How much is the radius of the lunar orbit around the Earth?