Answer:
I already helped with 1, and i don't know the answer to some of them, but here are some more:
Number 3 is actually a common riddle that exchanges 3 different animals/foods throughout cultures. Here's the wikipedia page for "wolf, goat, cabbage" with the solution to the riddle.
https://en.wikipedia.org/wiki/Wolf,_goat_and_cabbage_problem
here's the solution with the animals from your version put in. It works because the crocodile doesn't want to eat the peanuts.
1. Take the dove over
2. Return
3. Take the crocodile or peanuts over
4. Return with the dove
5. Take the peanuts or crocodile over
6. Return
7. Take dove over
and for number 6, the answer is the letter U.
<span>Before the alphabet was invented, early writing systems had been based on pictographic symbols known as hieroglyphics, or on cuneiform wedges, produced by pressing a stylus into soft clay. Because these methods required a plethora of symbols to identify each and every word, writing was complex and limited to a small group of highly-trained scribes. Sometime during the second millennium B.C.
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