The Owner of a Local Nightclub Has Recently Surveyed a Random

The owner of a local nightclub has recently surveyed a random sample of n = 250 customers of the club.She would now like to determine whether or not the mean age of her customers is greater than 30.If so, she plans to alter the entertainment to appeal to an older crowd.If not, no entertainment changes will be made.The appropriate hypotheses to test are:

A) $H _ { 0 } : \boldsymbol { \mu } \geq 30 \text { versus } H _ { 1 } : \boldsymbol { \mu } < 30 \text {. }$
B) $H _ { 0 } : \mu \leq 30 \text { versus } H _ { 1 } : \mu > 30 \text {. }$
C) $H _ { 0 } : \bar { X } \geq 30 \text { versus } H _ { 1 } : \bar { X } < 30$
D) $H _ { 0 } : \bar { X } \leq 30 \text { versus } H _ { 1 } : \bar { X } > 30$