NO LINKS OR BS ANSWERS. just please find the missing values with work shown! <3

Which of the following parabolas opens down?

Twelve different video games showing substance use were observed and the duration times of game play (in seconds) are listed below. the design of the study justifies the assumption that the sample can be treated as a simple random sample. use the data to construct a 99% confidence interval estimate of μ, the mean duration of game play. 4028 4316 4816 4650 4036 5010 4833 4331 4307

In right triangle xyz, the right angle is located at vertex y. the length of line segment xy is 12.4 cm. the length of line segment yz is 15.1 cm. which is the approximate measure of angle yzx? 34.8° 39.4° 50.6° 55.2°