I need help with solving these math problems please. I will give brainliest to whoever gets them correct

Renita analyzed two dot plots showing the snowfall during the winter months for city a and for city b. she found that the median snowfall is 5 inches less in city a than in city b. the mean snowfall is about 2 inches less in city a than in city b. which explains why there is a difference in the measures of center for the sets of data?

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

Having a hard time understanding this question (see attachment).