A lens has a power of -2.5D. What is the focal length and nature of the lens?

Doctor has presecribed a lens having power + 1.5D. What will be the focal length of the lens ? What is the type of the lens and what must be the defect of vision ?

If a spherical lens has a power of, -0.25 D, the focal length of this lens will be:

Doctor has prescribed a lens having power +1.5 D . What will be the focal length of the lens? What is the type of the lens and what must be the defect of vision?

Doctor has prescribed a lens having power +1.5D. What will be the focal length of the lens? What is the type of the lens and what must be the defect of vision?

The power of lens is 2.5 D . What is its focal length ?