For a point object,which of the following always produces a virtual image in air?

Consider the following statements regarding an object placed between the pole and the focus of a concave mirror: $I$. The image is real. $II$. The image is magnified. $III$. The image is erect. Which of the following is correct?

Consider a concave mirror of $10 \,cm$ focal length illuminated by an object kept at a distance of $25 \,cm$. The distance at which the image is formed and its magnification respectively are

An object placed in front of a concave mirror of focal length $0.15 \,m$ produces a virtual image,which is twice the size of the object. The position of the object with respect to the mirror is ........... $cm$. (in $.5$)

If the lateral magnification is $-2$ for a virtual object in a spherical mirror,then:

$A$ concave mirror forms a real image three times larger than the object on a screen. The object and screen are moved until the image becomes twice the size of the object. If the shift of the object is $6 \ cm$,find the shift of the screen and the focal length of the mirror.