Number 7: what do the lines on the shape mean

The mean finish time was 185.52 with a standard deviation of 0.327 minute. the winning car driven by chris finished in 185.13. the previous year race had a mean finish time of 110.3 with a standard deviation of 0.106. the winning car that year driven by karen finished in 110.13 minutes. find their respective z-scores. chris - z-score karen “- z-score

*segment an is an altitude of right ? abc with a right angle at a. if ab = 2root 5 in and nc = 1 in, find bn, an, ac.

Use the squared identities to simplify sin^2x cos^2x