An employee at a supermarket is giving out samples of cake, and his boss asks him to get opinions from 20 males and 20 females on the quality of the cake. The employee does not want to bother...

An employee at a supermarket is giving out samples of cake, and his boss asks him to get opinions from 20 males and 20 females on the quality of the cake. The employee does not want to bother shoppers, so he only gives the cake sample and requests participation from the first 20 males and 20 females who make eye contact with him. What type of sampling method is this employee using?