What is the molecular weight of a gas which diffuses 1/50 as fast as hydrogen​

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

Which of the following is not one of the steps in the scientific method a. hypothesize b. summarize c. analyze d. familiarize

Which of the following units is not an official si unit