The figure below shows contours of . Find the values of on the contours. They are equally spaced multiples of 10.

graph of four increasing concave down curves, the first starting at the origin, the second passing appoximately through (0.4,0), and the other two starting at decreasing intervals along the x-axis after that. The curves are labeled A-D from left to right, and The graph shows x- and y-values over the range [0,1].

Curve A:
Curve B:
Curve C:
Curve D:

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