How many NAND gates are used to form AND gate?

A gate allows the signals to pass through only when some logical conditions are satisfied.The output of a 2-input .NOR. gate is fed to a "NOT gate. Draw the logic circuit of this combi nation of gates and write the truth table for the output of the combination for all inputs.

Draw the symbol of NAND gate.

How many words, with or without meaning, can be formed using all the letters of the word 'FRIDAY', using each letter exactly once? How many of them have first letter is a vowel?

Consider 12 points on a plane of which five are collinear. How many triangles can be formed using the 12 points?

Given the digits 1,2,3 and 8 How many two digit numbers can be formed using the given digits?