Answer:

Step-by-step explanation:

20 : 0.75 = 40 : 1.5 = 80 : 3

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300x .02= 6
6x10=60
Therefore the answer is $360
We want to know when we brought it back in to the room. at that time
the temperature difference is 80 - 42 = 38 so we have to solve
<span>
38=9<span>e<span>^−.3344t</span></span></span> for t
this time we get
<span><span>38 / 9</span>=<span>e^<span>−.3344t</span></span></span>
<span>t=<span><span>ln(<span>38 / 9</span>)</span><span> / −.3344</span></span></span>
<span>t=−4.3</span>
so 4.3 minutes before 2:10