The suggested answer presented when I got this one wrong was "No, 1 needs to cook the egg." That's terrible written English. Numerals are only acceptable in a sentence when they are used to explicitly state quantities, or numerical constructs (math, phone numbers, etc.). This is wholly unnatural. "One" when it is used to refer to a person in a general statement, must be written as "one."
I think this variant was generated by Duolingo automatically, and there’s little course contributors can do with it.
It was suggested to you because your answer was closest to it (or at least Duolingo’s algorithm though it was what you were trying to type). The default answer is ‘No, the egg should be cooked!’.
That is what I thought it should be too... I honestly don't think our answer is really wrong, since Russian doesn't have a perfect transliteration into English, so translation will usually be somewhat subjective.. but this is just a mobile app, and they had to draw the line somewhere... Oh well. :)
As Anaphasiy said above, the egg is in the accusative (which for this neuter noun is the same as the nominative). A more literal translation would be 'No, it is necessary to cook the egg'. Your sentence would have the egg in the dative - яйцУ - 'It is necessary FOR THE EGG to cook'.
Yes, there is. Готовить is an Imperfective verb, and is about the continuous process of cooking (think on English Imperfect or continuous tenses, but as a different verb).
Пригатовить is a Perfective verb, and is about the final result of getting a meal ready, and implies a deadline for finishing the cooking (think on English perfect tenses, but as a different verb and not just a different inflection or using an auxiliary verb).
"No, egg needs to be cooked" is rejected, but to a native English speaker this is a valid way of talking about "egg" in a mass sense, and would be synonymous with "...eggs need to be..." In Russian, can't this be construed in the mass sense like картошка, or is it strictly "a/the egg"?