What is the correct answer for the following questions

9. Which of the following statement/s is/are correct: Select one: a. We can build the XOR gate using AND GATES and inverters b. We can build the XOR gate using NAND gates only. c. We can build the XOR using NOR gates only. d. All the answers are correct In Positive edge trigger D flip flop Select one: a. The clock should be changed from one to zero b. The clock should be changed from zero to one c. The clock is always zero d. The clock is always one 11. The full adder has 3 input and 2 output (S and Cout), we can express the sum s using Select one: a. 3 input AND b. 3 input NOR c. 3 Input NAND d. 3 input XOR 12. Which of the following statement is true about 3-bit binary adder-subtractor Select one: a. We need 3 full adders b. We need 3 XOR gates C. M bit control the operation d. All the answers are correct 13. If you want to counter that count from 0 to 7 , how many flip flop we need to implement this counter Select one a. 3 b. 7 c. 1 d. 2 14. Which of the following statement is correct on universal shift register Select one: a. We can use this register to rotate right b. We can clear the output c. We can set the output d. All the answers are correct