From which position of the object does a convex lens form virtual and erect image? Explain with the help of ray diagram.

Draw ray diagrams to represent the nature, position and relative size of the image formed by a convex lens for an object placed at $2{\mathrm{F}}_1$.

Draw ray diagrams to represent the nature, position and relative size of the image formed by a convex lens for an object placed between ${\mathrm{F}}_1$ and optical centre $\mathrm{O}$ of the lens.