Trigger on multiple table in Sql server

I have three table in sql server database

Tables are:-

1. StudentDtl(RollNo,Name,CourseCode,Semesester)

2. CourseMarkMaster(CourseCode,ToatalMarks,PassMarks)

3.StudentMarkDtl(RollNo,CourseCode, ObtainMarks,GraceMarks)

Maintain Grace Markss

create trigger for GraceMark

1. Grace-100 obtatinMarks is between 36-39

then grace is 4,3,2,1

2. RollNo should be mapped with table 1 use Store Procedure.

ObtainMarks not negative and not greater then TotalMarks

CoureseCode

CouresCode should be Mapped with table 2