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Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5

Rachel is studying the population of a particular bird species in a national park. she observes every 10th bird of that species that she can find in the park. her conclusion is that the birds living in the park who belong to that species generally feed on insects. rachel's sample is . based on the sample she picked, rachel's generalization is

Ashop has a sale that offers 20% off all prices. on the final day they reduce all the sale prices by 25% linz buys a ratio on the day. work out the overall percentage reduction on the price of the ratio