Why did the company not just give one group a placebo

A60-tooth gear is connected to a 72-tooth gear.if the smaller gear turns 12 times,how many turns does the larger gear make?

Identify the composition of oceanic and continental crystal rocks.in a model of earth’s interior,where would these rocks appear?

If t=tall and t=short what will be the physical appearance of the offspring the cross below? a.some will be tall and some will be short b.they will all be tall c.they will all be short d.they will be medium height