Table shows a list of courses and prerequisites. A topological sort of the courses is a list of courses in the order in which they could be taken to satisfy the prerequisite requirements.

Course Prerequisities

CENG $100$ MATH $120$

CENG $150$ MATH $140$

CENG $200$ CENG $100,$ CENG $150,$ ENG $110$

CENG $240$ CENG $200,$ PHYS $130$

ENG $110$ None

MATH $120$ None

MATH $130$ MATH $120$

MATH $140$ MATH $130$

MATH $200$ MATH $140,$ PHYS $130$

PHYS $130$ None

a$)$ Draw the the prerequiste structure of the table as a directed graph.

b$)$ Find the topological sort of the above table