A concert hall has the following numbers of seats in the first 5 rows. . 18 seats in row 1
• 21 seats in row 2
• 24 seats in row 3
• 27 seats in row 4
• 30 seats in row 5
As the row number increases, the number of seats continues to follow the same pattern, resulting in an arithmetic
sequence. Which explicit formula gives the terms of this sequence?

Ur environment is very sensitive to the amount of ozone in the upper atmosphere. the level of ozone normally found is 4.04.0 parts/million (ppm). a researcher believes that the current ozone level is not at a normal level. the mean of 2525 samples is 4.44.4 ppm with a standard deviation of 0.80.8. assume the population is normally distributed. a level of significance of 0.020.02 will be used. make the decision to reject or fail to reject the null hypothesis. answer tables