30 books were put into three equal stacks how many books were in each stack

This is really simple 10 books per stack 

10 books were in each stack because 30 divided by three is 10. I hope this help

11,440 acres.

Well first, find the area in miles. This is as simple as multiplying the length (3 1/4) by the width (5 1/2) to get 17 7/8. Now just multiply this by 640 to convert from square miles to acres. This gets you 11,440 acres.

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