Explain two ways that humans use electromagnetic waves.

Describe the path of a ray that approaches a mirror parallel to the principal axis.

Which lists the organs in the correct order as food passes from the mouth to anus?

On a day when the barometer reads 75.23 cm, a reaction vessel holds 250 ml of ideal gas at 20 celsius. an oil manometer ( ρ= 810 kg/m^3) reads the pressure in the vessel to be 41 cm of oil and below atmospheric pressure. what volume will the gas occupy under s.t.p.?