The exponential decay of an element is given by the following function:

Where is the amount of the element left after days, and is the initial amount of the element. If there are kg of the element left after days, what was the initial amount of the element?

If you deposit into a savings account which earns a yearly interest rate, how much is in your account after two years?

If you deposit into a savings account which compounds interest every month, what is the expression for the amount of money in your account after years if you earn a nominal interest rate of compounded monthly?

Stuff animals were a strange craze of the 90's. A Cat stuff animal with white paws sold for $6 in 1997. In 2015, the Cat will sell for $1015. What has been the approximate rate of growth for these stuff animal felines?

Suppose you took out a loan years ago that gains interest. Suppose that you haven't made any payments on it yet, and right now you owe on the loan. How much was the loan worth when you took it out?

There were 240mg of caffeine in the discontinued energy drink. The decay rate for caffeine in the human bloodstream is around 0.14. If Jackie drinks this energy drink around 8PM, how much caffeine will still be in her system at midnight?

The exponential decay of an element is given by the function

In this function, is the amount left after days, and is the initial amount of the element. What percent of the element is left after ten days, rounded to the nearest whole percent?

The exponential decay of an element is given by the function

where is the amount of the element after days, and is the initial amount of the element. If of the element are left after four days, how much of the element was there initially, to the nearest tenth of a kilogram?

The exponential decay of an element is given by the function:

In this function, is the amount of the element left after days, and is the initial amount of the element. If of the element is left after seven days, how much of the element was there to begin with, rounded to the nearest kilogram?

John opens a savings account and deposits into it. This savings account gains interest per year. After years, John withdraws all the money, and deposits it into another savings account with interest per year. years later, John withdraws the money.

How much money does John have after this year period? (Assume compound interest in both accounts)