Sometimes a person cannot clearly see objects close up or far away. to correct this type of vision, bifocals are often used. the top half of the lens is used to view distant objects and the bottom half of the lens is used to view objects close to the eye. a person can clearly see objects only if they are located between 34 cm and 180 cm away from his eyes. bifocal lenses are used to correct his vision. what power lens (in diopters) should be used in the top half of the lens to allow him to clearly see distant objects

The power of top half of the lens is 0.55 Diopters.

Explanation:

Since, the person can see an object at a distance between 34 cm and 180 cm away from his eyes. Therefore, 180 cm must be the focal length of the upper part of lens, as the top half of the lens is used to see the distant objects.

The general formula for power of a lens is:

Power = 1/Focal Length in meters

Therefore, for the top half of the lens:

Power = 1/1.8 m

Power = 0.55 Diopters

there are no correct statementd on the list of choices you provided.

the answer is ampere

the ampere is used to measure electricity. an ampere is a unit of electric current equal. a unit of measure for the flow of current in a circuit. one ampere is the amount of current flow provided when one volt of electrical pressure is applied against one ohm of resistance.