Answer 1

1. Font-family
The font family is the fonts sharing a common design style and are differentiate by character's shape/display.

->Example: Georgia, Helvetica, Times etc.

2. Font-Style
The font-style property on the other hand sets whether a font should be styled with a normal, italic, or oblique face from its font-family.

->Example: normal, italic, oblique etc

3. Font-weight
The font-weight determine whether the font style should be lighter or bolder.

->Example: normal, light or bold and you can use value ranging from 100 -700 (or 900 but only few browser support up to 900).

Hope I was able to answer your question.
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