How many words (with or without meaning) of three distinct letters of the English alphabets are there?

How many words (with or without meaning) of three distinct letters of the English alphabet are there?

How many words (with or without meaning) of three distinct letters of the English aphabets are there?

How many 3 letter words with or without meaning can be formed using 26 letters in English alphabet, if no letter is repeated?

How many words with or without meaning each of three vowels and two consonants can be formed from the letters of the word INVOLUTE.

How many 4-letter code words are possible using the first 10 letters of the English alphabet, if no letter can be repeated ?

How many 3-letter code words are possible using the first 10 letters of English alphabet if : letters are repeated ?

How many 3-letter code words are possible using the first 10 letters of English alphabet if : no letter can be repeated ?