Quickly Solve this riddle

7 - 4 + 3 * 0 + 1 = ?

Replace the question mark with the correct number in below Picture:

How is a fly different from a mosquito?

You Throw The Outside, Cook The Inside
Eat The Outside, Throw The Inside.

What Is It?

You and your two friends are working in a multinational company. How can you three find out the average salary of you all without disclosing your own salary to the other two?

What is always in front of you but can’t be seen?

John can eat 27 chocolates in an hour, Jacob can eat 2 chocolates in 10 minutes, and Jolly can eat 7 chocolates in 20 minutes. How long will it take them to share and eat a box of 120 chocolates whilst playing Chess?

I am a seven-letter word but if you remove four of my letters I will have one left. What word am I?

Consider this about a word: The first two letters signify a male, the first three letters signify a female, the first four letters signify a great, while the entire world signifies a great woman. What is the word?

The chance of Mr John winning the lottery is 10%. All participants lined up and Mr John is 4th in the row. The first three participants lose the lottery.

What is the chance of Mr John now?