下面分别是c=0.2,c=0.4,c=0.6时的代码
g1 = ParametricPlot[{0.2*Cos[t], 0.2*Sin[t] + 0.2}, {t, 0, 2 Pi}]，
g2 = ParametricPlot[{0.4*Cos[t], 0.4*Sin[t] + 0.4}, {t, 0, 2 Pi}]，
g3 = ParametricPlot[{0.6*Cos[t], 0.6*Sin[t] + 0.6}, {t, 0, 2 Pi}]，
show[g1, g2, g3]

ClearAll["Global`*"]
Table[x^2 + (y - c)^2 == c, {c, 0.2, 0.6, 0.2}] //
ContourPlot[#, {x, -2, 2}, {y, -2, 2}] &

(* method I *)
ContourPlot[
Table[x^2 + (y - c)^2 == c^2, {c, {0.2, 0.4, 0.6}}] //
Evaluate, {x, -2, 2}, {y, -2, 2}]
(* method II *)
ParametricPlot[
Table[{c*Cos[t], c*Sin[t] + c}, {c, {0.2, 0.4, 0.6}}] //
Evaluate, {t, 0, 2 Pi}, Axes -> False]