need help with these thanks again

You invested $4,500 in a project which gave you a return of 14.9% the 1st year.You were quite happy, but the 2nd year wasn't as good.You lost 6.8% that year.The 3rd year was better - you made 5.5% onthis investment.What was your annual average rate of return over the three years?

The 5-number summary for test # 2 is 14.4, 52.6, 61.2, 68.1, and 86.7.What is the left whisker?

The average closing price of a stock has been calculated to be $14 and the corresponding variance to be $473.What is the coefficient of variation?

Using Chebysheff's theorm, you have concluded that at least 77.66% of the 3,075 runners took between 60.5 and 87.5 minutes to complete the 10km race.What was the standard deviationof these 3,075 runners?

2,878 runners who took part in a 10km race had an average time of 1 hr and 11 minutes.The standard deviation was 12 minutes.Using Chebysheff's theorem,determineat least how many runnershad a running time between53 minutes and 89 minutes?