The ratio of white pens to green pens is 2 to 8. how many green pens are there if there are 18 white pens?

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Adepartment store purchases screen-printed t-shirts at a cost of $5 per shirt. they mark up the price 150% (making the selling price 250% of the store's purchase price) and put them on the sales floor. every month that a t-shirt doesn't sell, the store reduces the selling price by 25%.

How is the number of vertices for a prism related to the name of the prism