George wants to save money for a car. george invests $1,300 in an account that pays an interest rate of 7.5%.
how many years will it take for the account to reach $7.100? round you answer to the nearest one hundredth
a=p(1+r)^t.

The rate of decay of a radioactive substance depends upon the amount present initially. the mass y (mg) of the radioactive substance cobalt-60 present in a sample at time t (years) is represented by the exponential equation y=50e −0.1315 t . answer the following questions in complete sentences. 1. how does the exponential equation above compare to the equation for simple interest that is compounded continuously? explain the similarities. 2. what is the initial amount of cobalt-60 in the sample? 2. how much cobalt-60 is left after 8.4 years? show your work. 3. what would be the y-intercept of the graph? what does it represent? 4. after how many years will the amount of cobalt-60 left be 6.25 mg? explain what happens to the cobalt-60 after 50 years? 5. discuss some “real-world” examples and uses of cobalt-60

Ill mark the brainliest if you me with the these three questions 7,8,9

How many sides does a regular polygon have if each exterior angle measure is 45 degrees explain your answer, i really don't understand this.