Ineed you find 20 books that you checked out from the library as you are cleaning your room. you need to take 4 books back to the library, and you want to set them aside in a pile on your desk. â  how many ways can 4â  of the 20â  books be arranged in a pile?

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Colby and jaquan are growing bacteria in an experiment in a laboratory. colby starts with 50 bacteria in his culture and the number of bacteria doubles every 2 hours. jaquan starts with 80 of a different type of bacteria that doubles every 3 hours. let x equal number of days. colbys experiment follows the model: a.) y=50*2^x b.) y=50*2^8x c.) y=50*2^12x jaquans experiment follows the model: a.)80*2^x b.)80*2^8x c.)80*2^12x

Solve: 3x+y=6 4x-2y=18 show all work !