Answer:
Step-by-step explanation:
hola
Cuando dos numeros tienen el mismo signo la respuesta siempre es positiva. cuando un signo es positivo y e lotro es negativo la respuesta siempre sera negativa. Esta es la regla para multiplicar numeros con signos diferentes. el orden de los signos no importa en multiplicacon siempre va ha ser la misma respuesta.
1) I'm not sure what an open operation is.
2) D
3) No
4) Yes
5) D
6) hmm
7) there doesn't seem to be a 6 or 7
8) C
1 gallon = 16 cups
1 hour = 60 min
16 cups = 60 min
5 gallons =180 min/ 3 hrs
1 cup = 3.75 minutes
Answer:
(a)Length =2 feet
(b)Width =2 feet
(c)Height=3 feet
Step-by-step explanation:
Let the dimensions of the box be x, y and z
The rectangular box has a square base.
Therefore, Volume of the box
Volume of the box

The material for the base costs
, the material for the sides costs
, and the material for the top costs
.
Area of the base 
Cost of the Base 
Area of the sides 
Cost of the sides=
Area of the Top 
Cost of the Base 
Total Cost, 
Substituting 

To minimize C(x), we solve for the derivative and obtain its critical point
![C'(x)=\dfrac{0.6x^3-4.8}{x^2}\\Setting \:C'(x)=0\\0.6x^3-4.8=0\\0.6x^3=4.8\\x^3=4.8\div 0.6\\x^3=8\\x=\sqrt[3]{8}=2](https://tex.z-dn.net/?f=C%27%28x%29%3D%5Cdfrac%7B0.6x%5E3-4.8%7D%7Bx%5E2%7D%5C%5CSetting%20%5C%3AC%27%28x%29%3D0%5C%5C0.6x%5E3-4.8%3D0%5C%5C0.6x%5E3%3D4.8%5C%5Cx%5E3%3D4.8%5Cdiv%200.6%5C%5Cx%5E3%3D8%5C%5Cx%3D%5Csqrt%5B3%5D%7B8%7D%3D2)
Recall: 
Therefore, the dimensions that minimizes the cost of the box are:
(a)Length =2 feet
(b)Width =2 feet
(c)Height=3 feet