UCLA Extension's marketing department wants to study the effectiveness of their email campaign. The department surveyed 40 students randomly selected from a contact database. The survey shows 26 of the 40 students surveyed enrolled in one course because of reading the email. 8 of the 40 enrolled in three courses after reading the email, and 6 of the 40 did not enroll even after reading the email. The effectiveness of the email campaign is measured by course enrollment. Can you calculate the mean as a measure of central tendency