a) Redraw the logic diagram for the circuit below using the appropriate dual symbols to produce a circuit with the minimum number of basic gates only. [5m]
b) A small discussion room with one table and five chairs is opened for students daily. For each session, maximum of 3 female and maximum of 3 male students can enter the room. The rules for using the room is as follows: 
The room cannot be empty because there are always students waiting to use the room.
Single female student cannot enter the room.
Number of students allowed per session is minimum 2 and maximum 5.
(i) Design a combinational logic circuit to calculate the total number of students in each session. Implement the circuit using the minimum number of NAND gates only. [22m] Hint: Please use 3-input gates where possible.
(ii) List down all the combinations of students formation allowed for each session. [3m] 
a) Redraw the logic diagram for the circuit below using the appropriate dual symbols to produce a circuit with the minimum number of basic gates only. [5] A B Do Y D b) A small discussion room with one table and five chairs is opened for students daily. For each session, maximum of 3 female and maximum of 3 male students can enter the room. The rules for using the room is as follows: The room cannot be empty because there are always students waiting to use the room. Single female student cannot enter the room. Number of students allowed per session is minimum 2 and maximum 5. b) A small discussion room with one table and five chairs is opened for students daily. For each session, maximum of 3 female and maximum of 3 male students can enter the room. The rules for using the room is as follows: The room cannot be empty because there are always students waiting to use the room. Single female student cannot enter the room. Number of students allowed per session is minimum 2 and maximum 5. Female Total number of students per session Discussion Room Male (1) Design a combinational logic circuit to calculate the total number of students in each session. Implement the circuit using the minimum number of NAND gates only. [22m] Hint: Please use 3-input gates where possible. (ii) List down all the combinations of student's formation allowed for each session. [3m] a) Redraw the logic diagram for the circuit below using the appropriate dual symbols to produce a circuit with the minimum number of basic gates only. [5] A B Do Y D b) A small discussion room with one table and five chairs is opened for students daily. For each session, maximum of 3 female and maximum of 3 male students can enter the room. The rules for using the room is as follows: The room cannot be empty because there are always students waiting to use the room. Single female student cannot enter the room. Number of students allowed per session is minimum 2 and maximum 5. b) A small discussion room with one table and five chairs is opened for students daily. For each session, maximum of 3 female and maximum of 3 male students can enter the room. The rules for using the room is as follows: The room cannot be empty because there are always students waiting to use the room. Single female student cannot enter the room. Number of students allowed per session is minimum 2 and maximum 5. Female Total number of students per session Discussion Room Male (1) Design a combinational logic circuit to calculate the total number of students in each session. Implement the circuit using the minimum number of NAND gates only. [22m] Hint: Please use 3-input gates where possible. (ii) List down all the combinations of student's formation allowed for each session. [3m]
