PLEASE HELP ME I’LL GIVE BRILLIANCE TO YOU

Use the given information to determine the exact trigonometric value.

In a sale there is 25% of all prices a chair costs £45 in sale how much was it before the sale

How do you find p(a and b) if a and b are independent events for two or more actions, such as tossing a coin twice and finding p(heads and heads)? 2. how do you find p(a or b) if a and b are independent events for one action, such as spinning a four-color spinner once and finding p(red or blue)?