Students Who Failed Subjects

A mark below 40 is a fail. Return each student who failed at least one subject together with the number of subjects failed, ordered by student.

Table schema

Results(student VARCHAR(20), subject VARCHAR(20), marks INT)

Sample data

student | subject | marks
Asha | Math | 80
Asha | Sci | 35
Ben | Math | 60
Ben | Sci | 70
Chitra | Math | 30
Chitra | Sci | 20