It took sharon 85 minutes to wash three cars. she spent x minutes on each car and 10 minutes putting everything away. how long did it take sharon to wash each car?

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Logan wants to know how many skateboards have defective parts. he inspects 20,000 skateboards and keeps track of the number of defects per board. use his probability distribution table to find the expected value for defects on a skateboard.

Find the center and the radius of the circle with the equation: x^2-2x+y^2+4y+1=0?