Need now 100 points need 1 paragraph each explaining questions 9 and 10 will mark brainliest !

In which source of water would a wave travel the fastest? o ice o cold o room temperature o hot mark this and return save and exit next

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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