What are some of the uses of ultra-sound

Astudent is given an assignment to demonstrate diffraction. he takes a photograph of a straw in a glass of water. the straw appears bent at the water level. which best describes this example? a) this is a good example of diffraction. b) this is an example of dispersion and not diffraction. c) this is an example of refraction and not diffraction. d) this is an example of reflection and not diffraction.

The two required components for a generator are

Need asap ‼️ 20 pts which gravitational force field diagram is drawn correctly? (answers in pictures below)