Given that I no not see any explanation in the previos answer, I think you can benefit of this.
Exothermic refers only to the fact that the reaction releases energy in the form of heat when occurs. So, the enthalpy is higher at start and lower and the end.
Seen in this way, you can deduct that the change in enthalpy is negative, which is what the third option says.
The length of the altitude is 
Explanation:
Let ABC be an equilateral triangle.
It has sides of length 16 cm
Let AD be the altitude of the triangle.
We need to determine the length of an altitude.
Let AC = 16 cm and CD = 8 cm
Let us consider the right angled triangle ADC
Using the Pythagorean theorem, we have,
Substituting the values, we get,
The length of the altitude is
Problem 37
<h3>Answer: B. 4 & 1/4 gallons</h3>
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Work Shown:
The 3/4 and 1/2 add up to (3/4)+(1/2) = (3/4)+(2/4) = 5/4 = 1&1/4
The whole part 1 is then added to the other whole parts 1 and 2 to get 1+2+1 = 4
Overall, the grand total is 4 & 1/4
An alternative way is to convert each mixed number to a decimal to get 1&1/2 = 1+1/2 = 1+0.5 = 1.5 and 2&3/4 = 2+3/4 = 2+0.75 = 2.75
Add up those decimals 1.5+2.75 = 4.25
then convert that result to a mixed number: 4.25 = 4+0.25 = 4+1/4 = 4&1/4
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Problem 38
<h3>Answer: C. Cubic feet</h3>
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The units for volume follow the template "Cubic _____" where you'll write "feet", "inches", "centimeters" or whatever unit you are using in the blank.
Some other examples:
* cubic miles
* cubic meters
* cubic yards
Tan(61)= x/16 --> 16 x tan(61) = 59.89 = 59.9
Answer:
Step-by-step explanation:
