Answer:
T = 76.39°C
Explanation:
given,
coffee cup temperature = 95°C
Room temperature= 20°C
expression
temperature at t = 0
T(0) = 95°C
temperature after half hour of cooling
t = 30 minutes
T(30) = 61.16° C
average of first half hour will be equal to
![T = \dfrac{1}{30}[(20t - \dfrac{75 e^{\dfrac{-t}{50}}}{\dfrac{1}{50}})]_0^30](https://tex.z-dn.net/?f=T%20%3D%20%5Cdfrac%7B1%7D%7B30%7D%5B%2820t%20-%20%5Cdfrac%7B75%20e%5E%7B%5Cdfrac%7B-t%7D%7B50%7D%7D%7D%7B%5Cdfrac%7B1%7D%7B50%7D%7D%29%5D_0%5E30)
![T = \dfrac{1}{30}[(20t - 3750e^{\dfrac{-t}{50}}]_0^30](https://tex.z-dn.net/?f=T%20%3D%20%5Cdfrac%7B1%7D%7B30%7D%5B%2820t%20-%203750e%5E%7B%5Cdfrac%7B-t%7D%7B50%7D%7D%5D_0%5E30)
![T = \dfrac{1}{30}[(20\times 30 - 3750 e^{\dfrac{-30}{50}} + 3750]](https://tex.z-dn.net/?f=T%20%3D%20%5Cdfrac%7B1%7D%7B30%7D%5B%2820%5Ctimes%2030%20-%203750%20e%5E%7B%5Cdfrac%7B-30%7D%7B50%7D%7D%20%2B%203750%5D)
![T = \dfrac{1}{30}[600 - 2058.04 + 3750]](https://tex.z-dn.net/?f=T%20%3D%20%5Cdfrac%7B1%7D%7B30%7D%5B600%20-%202058.04%20%2B%203750%5D)
T = 76.39°C
The number of cans that would be considered lethal if 10g was lethal and there where 12oz in a can is 419 cans.
<h3>How to convert mass?</h3>
According to this question, caffeine concentration is 1.99 mg/oz.
1.99 milligrams can be converted to grams as follows:
1.99milligrams ÷ 1000 = 0.00199grams
This means that 0.00199grams per oz is the caffeine concentration.
If there were 12 oz in a can, then, 0.00199grams × 12 = 0.02388 grams in 1 can.
This means that if 10grams is considered lethal, 10grams ÷ 0.02388 grams = 419 cans would be lethal for consumption.
Therefore, the number of cans that would be considered lethal if 10g was lethal and there where 12oz in a can is 419 cans.
Learn more about conversion factor at: brainly.com/question/14479308
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Answer:
the yellow one
Explanation:
2 of the same elements resolute as the same element
Answer:
Well a s the temperature increases, at a certain point called the Curie temperature, a magnet will lose its strength completely. So once the metal cools, its ability to attract magnets returns, though its permanent magnetism becomes weak. In general heat is the factor that has the most effect on permanent magnets.Explanation:
