Find the radius of the circle

$$\left(x+1\right)^2+\left(y-3\right)^2=25$$  

Find the radius of the circle

$$\left(x-4\right)^2+\left(y+3\right)^{2\ }=28$$  

Find the center of the circle

$$x^2+y^2=98$$  

Find the center of the circle

$$x^2+y^2=98$$