Hello could someone answer this? Thank you

The price of an item has been reduced by 30%. the original price was $30. what is the price of the item now ?

Two angles are complementary. the large angle is 36 more than the smaller angle. what is the measure of the large angle?

Suppose you are an avid reader and are looking to save money on the cost of books instead of paying about $20 for each book, you decide to look into purchasing a kindle for $120 you can purchase e-books for about $5 each 1. find the slope-intercept equation for the cost of the hard copy of books using x to represent the number of books 2. find the slope-intercept equation for the cost of the kindle with cost of e-books using x to represent the number of books