The difference between the length of a mean solar day and a sidereal day is approximately .......... minutes.

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

During a total solar eclipse,the moon almost entirely covers the sphere of the sun. Write the relation between the distances and sizes of the sun and moon.

What is accuracy in measurement? Accuracy depends on which factors?

Write the ratio of the maximum and minimum time observed in the universe.

$A$ man wishes to estimate the distance of a nearby tower from him. He stands at a point $A$ in front of the tower $C$ and spots a very distant object $O$ in line with $AC$. He then walks perpendicular to $AC$ up to $B$,a distance of $100 \; m$,and looks at $O$ and $C$ again. Since $O$ is very distant,the direction $BO$ is practically the same as $AO$; but he finds the line of sight of $C$ shifted from the original line of sight by an angle $\theta = 40^{\circ}$ ($\theta$ is known as 'parallax'). Estimate the distance (in $m$) of the tower $C$ from his original position $A$.