Which of the following is not true about performing biological investigations?
a. reading and understanding the steps before conducting an experiment is necessary for safety.
b. scientists are trained to conduct their investigations safely.
c. the metric system and the revised si are based on multiples of 10.
d. most scientists do not use the metric system or si.

Assume that you are interested in separating short (200-400 bp) dna molecules from a pool of longer molecules in the 10,000-20,000 nucleotide range. you have two recipes for making your polyacrylamide gels: one recipe uses 1.5 percent agarose and would be considered a “hard gel,” while the other uses 0.5 percent agarose and would be considered a loose gel. which gel should you use to separate the short (200-400 bp) dna molecules from a pool of longer molecules in the 10,000-20,000 nucleotide range?