1/7 of 42 is smaller. 47/7= 6 < 18 = 36/2
The Carbon Dioxide in the atmosphere is only very small
relative to other gases. Typically, it only consists about 0.038 percent or
0.04 percent of the gases in the atmosphere.
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Even though it is only small, CO2 is very important since it is one of the
greenhouse gases which ensures that the Earth stays warm.</span>
45 min. - 4 peoples - 5 walls
? min. - 6 peoples - 4 walls
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180 min. - 1 man - 5 walls ⇒
36 min. - 1 man - 1 wall ⇒
6 min. - 6 peoples - 1 wall ⇒
24 min. - 6 peoples - 4 walls (answer)
