Focus and directrix of the parabola \[{{x}^{2}}=-8ay\] are [RPET 2001]

1.	Focus and directrix of the parabola \[{{x}^{2}}=-8ay\] are [RPET 2001]
A.	\[(0,\ -2a)\ \text{and}\ y=2a\]
B.	\[(0,\ 2a)\ \text{and}\ y=-2a\]
C.	\[(2a,\ 0)\ \text{and}\ x=-2a\]
D.	\[(-2a,\ 0)\ \text{and}\ x=2a\]
Answer» B. \[(0,\ 2a)\ \text{and}\ y=-2a\]

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Focus and directrix of the parabola \[{{x}^{2}}=-8ay\] are [RPET 2001]

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