Follicular and luteal phase lengths. â variability of menstrual cycle. attributable to follicular phase. â  Mean cycle length ranges from 27.3 to 30.1 days between ages 20 and 40 years, follicular. phase length is 13-15 days, and luteal phase length is less variable and averages. 13-14 days1-3.
Any sequence of seven successive natural notes, such as C-D-E-F-G-A-B, and any transposition thereof, is a diatonic scale. Piano keyboards are designed to play natural notes, and hence diatonic scales, with their white keys. A diatonic scale can be also described as two tetrachords separated by a whole tone.
14 The Basic Blues Scale This is the stripped down version of the 10 note blues scale example fromabove. You can count 7 notes but the last note is a high C which is arepeated C nevertheless so technically this is a 6 note scale.