Can someone pls explain this to me i am super dead tired today sorry

Ricardo ran the 400 meter race 3 times his fastest time was 54.3 seconds his slowest time was 56.1 seconds if his average time was 55.0 seconds what was his time for the third race

Someone me and explain! will award brainliest!

Sales personnel for skillings distributors submit weekly reports listing the customer contacts made during the week. a sample of 55 weekly reports showed a sample mean of 17.5 customer contacts per week. the sample standard deviation was 5.8. provide 90% and 95% confidence intervals for the population mean number of weekly customer contacts for the sales personnel. a. 90% confidence interval, to 2 decimals b. 95% confidence interval, to 2 decimals