So for example, if we have two cycles, two to the two is four copies. If we have three cycles, two to the eight is eight copies. And so forth. Now, about 20 to 30 of these cycles can take place within an hour. So we see that after an hour, we can form anywhere from millions to billions of copies of a single DNA segment. So we see that the polymerase chain reaction is very effective and very efficient in actually forming those copies and amplifying the DNA molecule that we're interested in.