Halley's comet has an elliptical orbit with major and minor diameters of 36.18 AU and 9.12 AU,

Question:

Halley's comet has an elliptical orbit with major and minor diameters of 36.18 AU and 9.12 AU, respectively (1 AU is 1 astronomical unit, the earth's mean distance from the sun). What is its minimum distance from the sun (assuming the sun is at a focus)?
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