need help with this two quieries in sql.

students(sid,name,age,gpa) // sid is the primary key

courses(cid,deptid, description) // cid,deptid is the primary key

professors(ssn,name,address,phone,deptid) // ssn is the primary key

enrollment(sid,cid,section,grade) cid makes reference to the courses table. // sid, cid, and section is the primary key

teaches(cid,section,ssn). cid, section makes reference to the enrollment table // cid, section is the primary key

Write a query that produces the following table:

Deptid	Sps	%A	%B	%C	%D	%F
cs
math

Where SPS is the average number of students in each section and column %A has the percentage of students that got an A, and so on, over all the courses offered by each department. Assume a small section have less than 30 students, medium sections have at least 30 but less than 80, and large sections have at least 80 students.