What is the lens-like structure present in the eye called?

Which of the following phenomena contributes significantly to the reddish appearance of the sun at sunrise or sunset?

Name the defects of vision of the human eye.

Explain why,when the sun is overhead at noon,it appears white?

$A$ person cannot see objects distinctly when placed beyond $2\, m$.
$(a)$ Identify the eye defect.
$(b)$ Give two reasons for this defect.
$(c)$ Calculate the power and nature of the lens he should be using to see the distant objects clearly.
$(d)$ Draw the ray diagrams for the defective and the corrected eye.

What happens to the lens and the ciliary muscles when you are looking at nearby objects?