Question: Each edge of a cubical box has length 1 m. The box contains nine spherical balls with the same radius r. The center of one ball is at the center of the cube and it touches the other eight balls. Each of the other eight balls touches three sides of a box. Thus the balls are tightly packed in the box. Find r.
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I need a detailed answer explaing why the answer is what it is. I know what the answer is I just don't understand how it is achieved so step by step soultion would be really helpful. Thanks so much in advance!!