Suppose a researcher wants to know whether a high protein diet causes children to learn better in school. half of the children in the study eat a high protein diet while the other half eats their normal diet. the control group consists of the:

the control group would be the children eating their normal diet

relative dating involves things like higher layers are most recent than rocks lower in the sequence. this can be extended to the known sequence of fossils. rocks containing rabbit fossils are later than those containing dinosaur fossils.  

absolute dating methods mainly use radioactive elements that have known rates of decay and produce recognizable products. for example potassium 40 decays to produce argon. once a rock has solidified the argon is trapped. by measuring the argon and potassium0 you can get an accurate number for the age.  

some other methods are good for archaeological ages. dendrochronology involves recognizing the sequence of tree rings. the orientation of magnetized particles in baked clay can be used to date a fire.

hope this .. .

find out why you don't need to aim at such a syllable pattern in english. you may have thought that haiku was supposed to be 5-7-5, so what's up with the logo by the gravitational pull of celestial objects, can touch us in unexpected ways.