What is inline style define of write the code

Question

Problem:

Question 1: What is inline style define of write the code?

Question 2: What are three levels of style sheets?

Question 3: What is the advantage of external style sheets over inline style?

Question 4: Where in the document is the link of an external style sheet ?

Question 5: Write the CSS code to have links bold without the default underline.

Question 6: What is the correct HTML for referring to an external style sheet?( write an example)

Question 7: What is the format of an inline style ? (Write an example)

Please provide description of your answers.