• A company wishes to test if the new software system installed improved the mean waiting time for a customer to talk to a service representative to less than 120 seconds. Is the following the correct hypothesis to test for this problem? H X = 120 H: X <120 O Yes, this hypothesis is the correct one to test O No, this hypothesis is incorrectly written

An individual can take either a scenic route to work or a non-scenic route. She decides that use of the non-scenic route can be justified only if it reduces the mean travel time by more than 9 minutes. (a) If ?1 refers to the mean travel time for the non-scenic route and ?2 to the mean travel time for the scenic route, what hypotheses should be tested?   ?1 − ?2 = −9 ?1 − ?2 < −9 ?1 − ?2 < −9 ?1 − ?2 > −9  ?1 − ?2 =−9     ?1 − ?2 ≠ −9 ?1 − ?2 = 9 ?1 − ?2 < 9 ?1 − ?2 = 9?1 − ?2 > 9   B) If ?1 refers to the mean travel time for the scenic route and ?2 to the mean travel time for the non-scenic route, what hypotheses should be tested?   ?1 − ?2 = −9?1 − ?2 < −9   ?1 − ?2 = −9?1 − ?2 > −9   ?1 − ?2 = −9?1 − ?2 ≠ −9   ?1 − ?2 = 9?1 − ?2 < 9   ?1 − ?2 = 9?1 − ?2 > 9

Need help writing a null hypothesis for the bivariate relationship shown in the SPSS output.

The results section of an article reports the following “IQ scores of the sample differ from the population mean of 100, single sample t (19) = 2.80, p < .05, two tail”. Based on this result, how many people were included in the sample? Select one: 20 21 19 38