Under certain conditions neon gases diffuse at a rate of 7.0 cm/s under the same conditions as an on known gas defuses at a rate of 4.9 per second what is the approximate molar mass of the unknown gas?

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line