It depends if Ashley was on the call for seconds too,if there can be a remainder , if so then it would be 3 min. and 47 sec.
This is very similar to the last question:-
0.51No = No e^_0.0001t
t = ln 0.51 / 0.0001
= 6733 years
For the first part remember that an equilateral triangle is a triangle in which all three sides are equal & all three internal angles are each 60°. <span>So x-coordinate of R is in the middle of ST = (1/2)(2h-0) = h
And for the second </span><span> since this is an equilateral triangle the x coordinate of point R is equal to the coordinate of the midpoint of ST, which you figured out in the previous answer. Hope this works for you</span>
Answer:

Step-by-step explanation:
Given: 
To convert: the given sum into product
Solution:
Use formula: 
![cosx + cos3x + cos5x + cos7x=2\cos \left ( \frac{x+3x}{2} \right )\cos \left ( \frac{x-3x}{2} \right )+2\cos \left ( \frac{5x+7x}{2} \right )\cos \left ( \frac{5x-7x}{2} \right )\\=2\cos (2x)\cos (-x)+2\cos (6x)\cos (-x)\\=2\cos (2x)\cos (x)+2\cos (6x)\cos (x)\\=2\cos x\left [ \cos (2x)+\cos (6x) \right ]](https://tex.z-dn.net/?f=cosx%20%2B%20cos3x%20%2B%20cos5x%20%2B%20cos7x%3D2%5Ccos%20%5Cleft%20%28%20%5Cfrac%7Bx%2B3x%7D%7B2%7D%20%5Cright%20%29%5Ccos%20%5Cleft%20%28%20%5Cfrac%7Bx-3x%7D%7B2%7D%20%5Cright%20%29%2B2%5Ccos%20%5Cleft%20%28%20%5Cfrac%7B5x%2B7x%7D%7B2%7D%20%5Cright%20%29%5Ccos%20%5Cleft%20%28%20%5Cfrac%7B5x-7x%7D%7B2%7D%20%5Cright%20%29%5C%5C%3D2%5Ccos%20%282x%29%5Ccos%20%28-x%29%2B2%5Ccos%20%286x%29%5Ccos%20%28-x%29%5C%5C%3D2%5Ccos%20%282x%29%5Ccos%20%28x%29%2B2%5Ccos%20%286x%29%5Ccos%20%28x%29%5C%5C%3D2%5Ccos%20x%5Cleft%20%5B%20%5Ccos%20%282x%29%2B%5Ccos%20%286x%29%20%5Cright%20%5D)
![cosx + cos3x + cos5x + cos7x=2\cos \left ( \frac{x+3x}{2} \right )\cos \left ( \frac{x-3x}{2} \right )+2\cos \left ( \frac{5x+7x}{2} \right )\cos \left ( \frac{5x-7x}{2} \right )\\=2\cos x\left [ \cos (2x)+\cos (6x) \right ]\\=2\cos x\left [2 \cos \left ( \frac{2x+6x}{2} \right )\cos \left ( \frac{2x-6x}{2} \right ) \right ]\\=2\cos x\left [ 2\cos (4x) \cos (-2x) \right ]\\=4\cos x\cos (4x)\cos (2x)](https://tex.z-dn.net/?f=cosx%20%2B%20cos3x%20%2B%20cos5x%20%2B%20cos7x%3D2%5Ccos%20%5Cleft%20%28%20%5Cfrac%7Bx%2B3x%7D%7B2%7D%20%5Cright%20%29%5Ccos%20%5Cleft%20%28%20%5Cfrac%7Bx-3x%7D%7B2%7D%20%5Cright%20%29%2B2%5Ccos%20%5Cleft%20%28%20%5Cfrac%7B5x%2B7x%7D%7B2%7D%20%5Cright%20%29%5Ccos%20%5Cleft%20%28%20%5Cfrac%7B5x-7x%7D%7B2%7D%20%5Cright%20%29%5C%5C%3D2%5Ccos%20x%5Cleft%20%5B%20%5Ccos%20%282x%29%2B%5Ccos%20%286x%29%20%5Cright%20%5D%5C%5C%3D2%5Ccos%20x%5Cleft%20%5B2%20%5Ccos%20%5Cleft%20%28%20%5Cfrac%7B2x%2B6x%7D%7B2%7D%20%5Cright%20%29%5Ccos%20%5Cleft%20%28%20%5Cfrac%7B2x-6x%7D%7B2%7D%20%5Cright%20%29%20%5Cright%20%5D%5C%5C%3D2%5Ccos%20x%5Cleft%20%5B%202%5Ccos%20%284x%29%20%5Ccos%20%28-2x%29%20%5Cright%20%5D%5C%5C%3D4%5Ccos%20x%5Ccos%20%284x%29%5Ccos%20%282x%29)
Using the inequality
2.50x + 3.50y ≤ 30
substituting y with the number of cheeseburgers sold
2.5x + 3.5(4) ≤ 30
x = 6.4
The maximum number of hamburgers he can sell is 6