Your baby brother has an ear infection. The doctor said there are probably 50,000 bacteria in his left ear. The penicillin the doctor prescribed will kill 7% of the bacteria every hour. About how long will it take for there to be less than 25,000 bacteria?​

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?