The polymerase chain reaction is the means of producing multiple copies of the DNA segment from only a minute amount of original DNA. Procedure consists of the sequence of, say, 35 cycles in which each segment present at beginning of the cycle is duplicated once; at end of cycle which segment and one copy is present.
Asusme you start 4 picograms = 4×1012 g. of DNA.
Determine number of grams of DNA would be present after N cycles?