the Answer: Hubble's brilliant observation was that the redshift of galaxies was directly proportional to the distance of the galaxy from earth. That meant that things farther away from Earth were moving away faster. In other words, the universe must be expanding. He announced his finding in 1929.
The answer is: "dichotomous key" . _________________________________________________________ " A series of paired statements that described physical characteristics of different organisms is a <u> dichotomous key </u><u /> . " _________________________________________________________
You would have to be very careful of cross-contamination. That means you would have to work very carefully and precisely with protective clothing, ensuring that none of your DNA (from skin or hair or even trace) gets into the sample you are working with
You would have to be very careful to check and record samples properly to ensure nothing got mixed up or mislabeled and this could be disastrous for criminal cases
All the material is very precious and sometimes only one sample exists, so you have to avoid making any mistakes. Experiments can't always be repeated.
