Find the radius of the following circle

x^2+16+y^2-4y+16=0

The perimeter of a rectangle is greater than or equal to 74 meters. if the length is 25 meters, the minimum width of the rectangle is meters.

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

Okay so i didn't get this problem petro bought 8 tickets to a basketball game he paid a total of $200 write an equation to determine whether each ticket cost $26 or $28 so i didn't get this question so yeahyou have a good day.