Translation:It takes eleven months.
Small keThe small ke is a common Japanese character, typographically a small form of the katakana character ケ ke. While identical in shape to a small ケ, the shape is actually an abbreviation for the kanji 箇, specifically by writing half of the bamboo radical 竹, and ヶ is used as an abbreviation 箇 (alternatively written 個 or 个), which is a common Japanese counter word. It is also as an abbreviation for the Japanese conjunctive particle が.
Theres no reason other than its not listed as an acceptible translation. Please continue to report it until it gets added. I end up at the end of the lesson with a dozen of these and it refuses to accept my "it will", so I report them each a few times then deal with the nonsense that its demanding.