In order to explore the efficiency of Venlafaxine and Fluoxetine on geriatric depression, the patients were divided into two groups, one group were treated with the Venlafaxine(group 1) ,the other were treated with Fluoxetine(group 2).Of the 30 patients in group 1, 19 were effective and 11 were not. Of the 30 patients in group 2, 15 were effective and 15 were not. (1) Create a 2 by 2 frequency table according to the question.(4’)
(2)Which kind of hypothesis test can be used to find out difference between the two kinds of treatment?( list all the steps of the test and calculation was not needed.