PLEASE HELP ME PLEASE ! there is a rectangular padding pool of constant depth the pool is filled with sea water.
(a) the volume of the sea water in the pool is 264mcube . calculate the depth of the pool.
(b) the mass of the sea water is 2.70x10power 5 kg calculate the density of the sea water. ( give the answer in 3 significant figures)

An object is located 30.0 cm from a concave mirror. the focal length is 15.0 c,. what is the image distance? a. 30.0 cm b. -10 cm c. 10.0 cm d. -30.0 cm

What is the earliest point in the universe that we can observe? why can’t we see back further than this?

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.