Other mistake: In the beginning, Eric reads to Hanna from an encyclopedia. He first talks about the blue whale. Hanna asks him about music and then he turns two pages further and reads the article about music. This is impossible if he was looking up the whale under the letter "W", because he then would have had to turn a lot of pages back, instead of further. Also, had the entry been under the letter "B" from blue, it would have been further than 2 pages. He could not have been looking up the word "Mammal", because there would not be more than the mentioning of the name "Whale" under that description, and not an entire explanation plus picture of this animal like in the movie. If he would want info on the Whale like the info he read, he would have had to look it up under the letter "W", this is true in any encyclopedia.
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