-Five hours after the start of an experiment, there were 600 bacteria, and 5 hours after that there were 720 bacteria.

a. Write the formula for N, the number of bacteria "t" hours after the start of the experiment if it follows a linear relationship

b. Write the formula for N, the number of bacteria "t" hours after the start of the experiment if it follows an exponential relationship

c. If it is exponential, when will there be 1000 bacteria?

-The half-life of carbon-14 is 5730 years. How long would it take for a sample to decay to 10% of the original amount?

-If 90% of a sample of a radioactive material remains after 7 days, find the time it takes for half-life to occur.