In the group of ordered pairs shown, the x-values are inputs and the y-values are outputs. Which statements are true about the inputs and outputs? Select all that apply. (2, 4), (6, 3), (5, 4), (7, 3), (8, 2)

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

Will mark ! (10 points also! ) if x varies inversely with y and x =6 when y= 10, find y when x=8 a. y=4.8 b. y=7.5 c. y=40/3 d. y=4/15

The correlation coefficient between the number of students and marks obtained in end semester exam. (13 marks) give the statistical meaning of the relationship between the number of students and marks b. obtained in end semester exam. (3 marks) draw the number of students and marks obtained in end semester exam scatter diagram c. (4 marks) check list write your name and id corectly write the question number properly use your own calculator. show all the steps to solve the problems. use the correct formula. answer in provided time. don't use your mobile for any purpose. write your answer up to two decimal places