What is the value of the 30th term in the following arithmetic sequence?

12, 6, 0, -6, ...

John can eat 10 cookies in 1/2 hr how many cookies can he eat in 45 minutes make a proportion and solve

The first-serve percentage of a tennis player in a match is normally distributed with a standard deviation of 4.3%. if a sample of 15 random matches of the player is taken, the mean first-serve percentage is found to be 26.4%. what is the margin of error of the sample mean? a. 0.086% b. 0.533% c. 1.11% d. 2.22%

Plz hurry evaluate the expression a+b where a=8 and b=19