How many moles are in 4.21 x 10^20 atoms of He? OA) 2.53 x 1044 mol
O B) 25.3 mol
O C) 6.99 x 10-4 mol
OD) 1.69 x 1021 mol

All motion is caused by force? true or false

You wish to prepare a buffer consisting of acetic acid and sodium acetate with a total acetic acetate plus acetate concentration of 250 mm and a ph of 5. what concentrations of acetic acid and sodium acetate should you use

Ascientist wants to know how individual lions within a pride interact with each other in their own environment. to do this, the scientist sedates and tags all of the lions within a pride. then, he places several remotely-controlled video cameras near the lions' den and performs an observational field study. he collects continuous video footage over the span of one year, analyzes the video, and then forms conclusions based on his observations.