The human body is an organism made up of cells, tissues, organs, and organ system. here are examples of three types of muscle tissue that are made of very different cells. how can scientists determine what type of cells make up each of these three tissues? a) by using a magnifying glass to observe each tissue. b) by collecting the tissues of people who have died and making observations. c) by dissecting the tissues and then making observations using a dissecting scope. eliminate d) by placing samples of each tissue on a slide and viewing the slides using a microscope.

Uranium has two naturally occurring isotopes. 238u has a natural abundance of 99.3% and 235u has an abundance of 0.7%. it is the rarer 235u that is needed for nuclear reactors. the isotopes are separated by forming uranium hexafluoride uf6, which is a gas, then allowing it to diffuse through a series of porous membranes. 235uf6 has a slightly larger rms speed than 238uf6 and diffuses slightly faster. many repetitions of this procedure gradually separate the two isotopes. what is the ratio of the rms speed of 235uf6 to that of 238uf6? express your answer to five significant figures.