A colony of E. Coli in a lab doubles in number every 20 minutes through cell division. How many *HOURS* would it take for 1 cell of E. Coli to become 100 cells in a petri dish?

You just purchased two coins at a price of $670 each. because one of the coins is more collectible, you believe that its value will increase at a rate of 7.1 percent per year, while you believe the second coin will only increase at 6.5 percent per year. if you are correct, how much more will the first coin be worth in 15 years?