Ascientist begins a pcr with 10 picograms of dna and allows it to go through three cycles.
how much dna, in picograms, does the scientist have at the end of three cycles?
a. 10 b. 80 c.40 d.20

b. 80g

Explanation:

Three cycles of PCR would produce 3 doublings of the amount of DNA.

Cycle 1: 10x2  = 20pg

Cycle 2: 20x2 = 40pg

Cycle 3: 40x2 = 80pg

This can also be worked out for large cycle numbers by final mass = starting mass x 2ⁿ, where n is the number of cycles.

the answer is; comparing the frequency of collisions with and without the device

this makes the anti-collision system an independent variable and the collisions a dependent variable. if there are fewer collisions with an anti-collision system that without, then it can be stated that the system is a success. essentially, collisions under an anti-collision system are compared with the frequency of collisions by cars with the human drivers.