How many different license plates can be created using three letters followed by four digits?

Zahra was given two data sets, one without an outlier and one with an outlier. data without an outlier: 15, 19, 22, 26, 29 data with an outlier: 15, 19, 22, 26, 29, 81

33% of college students say they use credit cards because of the rewards program. you randomly select 10 college students and ask each to name the reason he or she uses credit cards. find the probability that the number of college students who say they use credit cards because of the rewards program is (a) exactly two, (b) more than two, and (c) between two and five inclusive. if convenient, use technology to find the probabilities.

Can someone tell me if this is perpendicular? !