At what angle (in degrees) should two plane mirrors be inclined to obtain $3$ images?

With reference to the figure shown below, match the following:

$(a)$ Angle of reflection	$(i)$ $60^\circ$
$(b)$ Value of $\alpha$	(ii) $120^\circ$
$(c)$ Angle of deviation	(iii) $30^\circ$

$A$ person runs with a speed $u$ towards a bicycle moving away from him with speed $v$. The person approaches his image in the mirror fixed at the rear of the bicycle with a speed of:

When a plane mirror is rotated through an angle $\theta$,the reflected ray turns through an angle $2\theta$. What happens to the size of the image?

$A$ point source of light $S$ is placed at a distance $10\,cm$ in front of the centre of a mirror of width $20\,cm$ suspended vertically on a wall. $A$ man walks with a speed $10\,cm/s$ in front of the mirror along a line parallel to the mirror at a distance $20\,cm$ from it as shown in the figure. Find the maximum time during which he can see the image of the source $S$ in the mirror. (in $,s$)

An object is initially at a distance of $100 \; cm$ from a plane mirror. If the mirror approaches the object at a speed of $10 \; cm/s$,then after $6 \; s$,the distance between the object and its image will be: (in $; cm$)