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Puzzle 17
There are three houses, and three utilities: water, gas, and electricity.
Your task is to connect each house to all three utilities.
Therefore, each house will have three lines, and each utility will also have three lines.
However, you cannot cross lines! You cannot pass lines through houses or utilities. You cannot share lines.
Can you draw the 9 lines required?
??
Puzzle 18
Can you find three common words which …
… contain EE twice?
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Puzzle 19
What number comes next in the sequence:
11 · 13 · 17 · 31 · 37 · 71 · 73 · 79 · 97 · ?
?
Puzzle 20
This is a very special sequence and is complete, but what is the missing letter?
T · I · A · V · S · S · A · I · C · ? · W · I · T · M · L