Describe a scenario where an x-ray technologist could encounter an off-level grid error

Which describes an image that can be produced by a concave lens? the image is real and smaller than the object. the image is virtual and larger than the object. the image is virtual and smaller than the object. the image is real and larger than the object.

The mass of a bowling ball is 10 kg and the mass of a ping pong ball is 0.015 kg. if the two objects are 5 meters apart, what is the gravitational force ?

Specific heat refers to the amount of heat required to change 1 gram of a substance by degree(s) celsius