Answer:
Domain![=\{1,2,3,4,5,6,7,8,9,10,11,12,,13,14,15,16,17,18,19,20\}](https://tex.z-dn.net/?f=%3D%5C%7B1%2C2%2C3%2C4%2C5%2C6%2C7%2C8%2C9%2C10%2C11%2C12%2C%2C13%2C14%2C15%2C16%2C17%2C18%2C19%2C20%5C%7D)
In other words Domain![=\{x|x\ is\ an\ integer\ and\ 1\leq x\leq20\}](https://tex.z-dn.net/?f=%3D%5C%7Bx%7Cx%5C%20is%5C%20an%5C%20integer%5C%20and%5C%201%5Cleq%20x%5Cleq20%5C%7D)
Step-by-step explanation:
![C(x)=80-4x](https://tex.z-dn.net/?f=C%28x%29%3D80-4x)
Let after
weeks she has left no money.
![c(t)=0\\80-4t=0\\4t=80\\t=20](https://tex.z-dn.net/?f=c%28t%29%3D0%5C%5C80-4t%3D0%5C%5C4t%3D80%5C%5Ct%3D20)
That means she can have money for ice cream from the week 1 to week 20 and after that she will have no money.
So
can be any number between
and ![20](https://tex.z-dn.net/?f=20)
Hence Domain![=\{x|x\ is\ an\ integer\ and\ 1\leq x\leq20\}](https://tex.z-dn.net/?f=%3D%5C%7Bx%7Cx%5C%20is%5C%20an%5C%20integer%5C%20and%5C%201%5Cleq%20x%5Cleq20%5C%7D)
Q= 3456
because, 3=4+7
4+5=9
5+6=11
and 3 x 2=6
Answer:
25
Step-by-step explanation:
(60*25)/100 is the equation
Answer: ![\bold{d)\quad y = 3 cos (\dfrac{4}{3}x-2\pi) + 2}](https://tex.z-dn.net/?f=%5Cbold%7Bd%29%5Cquad%20y%20%3D%203%20cos%20%28%5Cdfrac%7B4%7D%7B3%7Dx-2%5Cpi%29%20%2B%202%7D)
<u>Step-by-step explanation:</u>
![\text{Period = }\dfrac{2\pi}{B}\\\\\\\dfrac{1}{2}\text{Period = }\dfrac{1}{2}\cdot \dfrac{2\pi}{B}\quad =\dfrac{2\pi}{2B}\\\\\\\text{In the given equation, B = }\dfrac{2}{3}\implies 2B=\dfrac{2\cdot 2}{3}\quad =\dfrac{4}{3}\\](https://tex.z-dn.net/?f=%5Ctext%7BPeriod%20%3D%20%7D%5Cdfrac%7B2%5Cpi%7D%7BB%7D%5C%5C%5C%5C%5C%5C%5Cdfrac%7B1%7D%7B2%7D%5Ctext%7BPeriod%20%3D%20%7D%5Cdfrac%7B1%7D%7B2%7D%5Ccdot%20%5Cdfrac%7B2%5Cpi%7D%7BB%7D%5Cquad%20%3D%5Cdfrac%7B2%5Cpi%7D%7B2B%7D%5C%5C%5C%5C%5C%5C%5Ctext%7BIn%20the%20given%20equation%2C%20B%20%3D%20%7D%5Cdfrac%7B2%7D%7B3%7D%5Cimplies%202B%3D%5Cdfrac%7B2%5Ccdot%202%7D%7B3%7D%5Cquad%20%3D%5Cdfrac%7B4%7D%7B3%7D%5C%5C)
The only option that has B = 4/3 is the last one.