3. (3 points) (a) In the complete expansion of (m+n+o). (p+g+r+s). (t+w+v+w+z), one obtains terms such as mpt, nqw, and ort. How many such terms appear in this complete expansion? (b) Which of the following terms do not appear in the complete expansion from part (a)? i. mur ii. nuu iii. our iv. ntw v. pqv vi. orz

Fig: 1