Answer: 22 hours 11 minutes
<u>Step-by-step explanation:</u>

![22\ hours + \bigg[\dfrac{19}{100}=\dfrac{x}{60}\bigg]\\\\22\ hours + 11\ minutes](https://tex.z-dn.net/?f=22%5C%20hours%20%2B%20%5Cbigg%5B%5Cdfrac%7B19%7D%7B100%7D%3D%5Cdfrac%7Bx%7D%7B60%7D%5Cbigg%5D%5C%5C%5C%5C22%5C%20hours%20%2B%2011%5C%20minutes)
B) Is the correct answer
We know it's B because it's a one off cost and isn't effected by x ( the amount of songs purchased )
Answer:
18 cups of lemonade
Step-by-step explanation:
so if it cost him $0.15 to make each cup of lemonade and he sold a cup for $0.35 then he sold 18 cups
1. Given any triangle ABC with sides BC=a, AC=b and AB=c, the following are true :
i) the larger the angle, the larger the side in front of it, and the other way around as well. (Sine Law) Let a=20 in, then the largest angle is angle A.
ii) Given the measures of the sides of a triangle. Then the cosines of any of the angles can be found by the following formula:
a^{2}=b ^{2}+c ^{2}-2bc(cosA)
2.
20^{2}=9 ^{2}+13 ^{2}-2*9*13(cosA) 400=81+169-234(cosA) 150=-234(cosA) cosA=150/-234= -0.641
3. m(A) = Arccos(-0.641)≈130°,
4. Remark: We calculate Arccos with a scientific calculator or computer software unless it is one of the well known values, ex Arccos(0.5)=60°, Arccos(-0.5)=120° etc