PLEASE HELP ASAP start off by restating: Historians know about the past before there were written records by studying artifacts The three main types of artifacts are physical, visual, and oral traditions.

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

Round each of the decimals to the nearest hundredth a. 0.596 b. 4.245 c. 53.6843 d. 17.999

How can you check that you have correctly converted frequencies to relative frequencies?