How many people teaches course no.11?
people refers to taughtBy.p_id; course no.11 refers to course_id = 11
SELECT COUNT(*) FROM taughtBy WHERE course_id = 11
database name:db_id computer_student
course table course Cols: course id dtype integer, course level dtype text, 
person table person Cols: person ID dtype integer, professor dtype integer, student dtype integer, has position dtype text, in phase dtype text, years in program dtype text, 
advisedBy table advisedBy Cols: person id dtype integer, person id dummy dtype integer, 
taughtBy table taughtBy Cols: course ID dtype integer, person ID dtype integer, 
