Using distributive property, write an equivalent expression for 21x + 7 PL

Asap! i'm not good math and i'm lost.

The sides of a parallelogram are 24cm and 16cm. the distance between the 24cm sides is 8 cm. find the distance between the 16cm sides

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