Answer
(a) $(h,k)=(0,0)$ $r=2$.
(b) See graph.
(c) $(\pm2,0)$, $(0,\pm2)$.
Work Step by Step
(a) Given $x^2+y^2=4$, we can find the center $(h,k)=(0,0)$ and radius $r=2$.
(b) See graph.
(c) We can find the x-intercept(s) (let y=0) $(\pm2,0)$, y-intercept(s) (let x=0) $(0,\pm2)$.
