What should be the next letter in the following series? a z e b i y o _ ? _

 c

Step-by-step explanation:

Notice the pattern (vowel, consonant, vowel, consonant):

A: first vowel            z: last consonant

e: second vowel                                        b: first consonant      

i: third vowel             y: second to the last consonant

o: fourth vowel                                           c: second consonant

i think the length is 12 and the width is 17