Between 15 and 20 are under 6 feet ( 1.8 m ) high , slightly more than 10 are 6 to 9 feet ( 1.8 to 2.7 m ) high .
Approximately three are over 9 feet ( 2.7 m ) high .
Between 15 and 20 are under 6 feet ( 1.8 m ) high , slightly more than 10 are 6 to 9 feet ( 1.8 to 2.7 m ) high , and approximately three are over 9 feet ( 2.7 m ) high .