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There is a planet named Eskerard, which has 170 light years away from us. The people there nave 8 hands but each with only 1 finger. The government there has issued a set of money notes $1, 2, 4, 8, 16, 32, 64, 128.

Can you help them find out how to combine the notes in order to pay the following bills after meal?

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Given that there that there are 100 light bulbs labeled 1 to 100 with 100 corresponding switcher, pressing it once to switch on the bulb and pressing it agin to switch off the bulb. At first, all the bulbs were off. Now, there are 100 students take turns to press the light bulb swichers.

The first student presses the switchers labeled with an even number and this time bulbs labelled with an even number are off.

The third student presses switchers labeled with a number divisible by 3 thus some ligth bulbs are on and some are off by then. This process goes on until the last turn has finished (i.e., the 100th student has pressed the switchers).

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