The task of science to fourth grade

Solves this problem semёy.Raspisali all three of the most optimal solution, because each of us was sure that his decision is the right (in any case remain permanently redundant tigers and elephants). The child with pleasure executed this task, went to school with joy, and come with a deuce. Son still can not understand, for which he put a deuce. And I want to know how to solve this problem, to her! Can anyone help? And then, maybe I should not going to school tomorrow?




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