You raise an apple to a higher position. The apple starts and ends at rest. The net work done on the apple is: [ ] positive [ ] negative [ ] zero The work done by you on the apple is: [ ] positive [ ] negative [ ] zero The work done by gravity on the apple is:

If the radius of curvature of the cornea is 0.75 cm when the eye is focusing on an object 36.0 cm from the cornea vertex and the indexes of refraction are as described before, what is the distance from the cornea vertex to the retina? express your answer to two significant