If a typical molecule has 10^(25) parts and someone wanted to artificially build them at a rate of a million parts per second, how long would it take to complete just one molecule? What is this problem called and why?

1 cancel("molecule") × (10^25 cancel("parts"))/(1 cancel("molecule")) × (1 cancel("s"))/(10^6 cancel("parts")) × (1 cancel("min"))/(60 cancel("s")) × (1 cancel("h"))/(60 cancel("min")) × (1 cancel("day"))/(24 cancel("h")) × "1 yr"/(365.24 cancel("days")) = 10^11"yr"