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Answer for 10 points show work you guys in advanced < 3

40) linda was making chocolate truffles for the first day of school. the recipe for 20 chocolate truffles is: i cup of cream 2 cups of dark chocolate she noticed this will not be enough truffles for the 42 sure that all students in each homeroom next year. to be sure that all students receive a truffle, linda must adjust her recipe. a. complete the recipe for 42 truffles cups of cream - cups of dark chocolate work:

Calculate the average rate of change over the interval [1, 3] for the following function. f(x)=4(5)^x a. -260 b. 260 c. 240 d. -240