What is hypermetropia ? What are the causes of this defect ? How can this defect of the eye be corrected ?

What is hypermetropia? What are the causes and how is it rectified?

What is short sightedhess or myopia? What are the causes of this defect? By which lens this defect can be corrected?

a) What is hypermetropia? What are the two causes of theis defect of vision. b) What is the colour of the clear sky during day time. Give reason for it.

How the defect of astigmatism can be corrected ?

What is myopia ? What are the reasons that arise this defect ? How can you rectify this defect ?