Given the function f (a, y)-422 + 6xy 5y hat is df(x,) dr given the function f (x, y)42 6zy 5y what is day)? given the function f (a, y) -422 +6zy 5y what is ) given the function f (z, y) = 4x2 + 6xy-5y2 what is du? given the function f (x, y) 4x2 + 6xy-5y2 what is u) dy dz2 2 drdy

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