What is the primary purpose of the eyepiece in a telescope?

In a Galilean telescope,if the powers of an objective and eye lens are respectively $+1.25 \, D$ and $-20 \, D$,then for relaxed vision,the length and magnification will be

The angular magnification of an astronomical telescope is $10$. The final image is formed at infinity. The length of the telescope is $44 \, cm$. The focal length of the objective lens is .......... $cm$.

The focal length of the objective and eye lens of an astronomical telescope are $2 \, m$ and $5 \, cm$ respectively. The final image is formed at $(i)$ the least distance of distinct vision and $(ii)$ infinity. The magnifying power in both cases will be:

Diameter of the moon is $3.5 \times 10^3 \, km$ and its distance from earth is $3.8 \times 10^5 \, km$. It is seen by a telescope whose objective and eyepiece have focal lengths $4 \, m$ and $10 \, cm$ respectively. What will be the angular diameter of the image of the moon in degrees?

In an astronomical telescope,the focal length of the objective lens is $100 \, cm$ and of the eyepiece is $2 \, cm$. The magnifying power of the telescope for the normal eye is: