A.  x2/a4+y2/b4=1/r4

B.  x2/a4+y2/b4=1/r2

C.  y2/a4+x2/b4=1/r2

D.  x2/a4+y2/b4=-1/r2

Correct Answer :
x2/a4+y2/b4=1/r2
Explanation :
No Explanation available for this question
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