Which mirror has a large field of view?

When an object is placed at the center of curvature $(C)$ in front of a concave mirror,what kind of image is formed?

Rays from the Sun converge at a point $15 \, cm$ in front of a concave mirror. Where should an object be placed so that the size of its image is equal to the size of the object?

$A$ convex mirror used on an automobile has $3\, m$ radius of curvature. If a bus is located at $5\, m$ from this mirror,find the position,nature,and size of the image.

$A$ $10\, mm$ long awl pin is placed vertically in front of a concave mirror. $A$ $5\, mm$ long image of the awl pin is formed at $30\, cm$ in front of the mirror. The focal length of this mirror is ......... $cm$.

$(i)$ Describe an activity to find the approximate value of the focal length of a concave mirror.
$(ii)$ What happens to the size of the image of an object when it is moved gradually away from a convex mirror?
$(iii)$ In an experiment to study refraction through a glass slab,it is observed that a ray of light undergoing refraction emerges parallel to the direction of the incident ray. Why does it happen so? Explain with the help of a diagram.