7/10 is bigger because it is more than half
Answer:

Step-by-step explanation:
Let
Side of square base=x
Height of rectangular box=y
Area of square base=Area of top=
Area of one side face=
Cost of bottom=$9 per square ft
Cost of top=$5 square ft
Cost of sides=$4 per square ft
Total cost=$204
Volume of rectangular box=
Total cost=



Substitute the values of y

Differentiate w.r.t x







It takes positive because side length cannot be negative.
Again differentiate w.r. t x

Substitute the value

Hence, the volume of box is maximum at x=2.2 ft
Substitute the value of x

Greatest volume of box=
Answer:
A) $2.42, $2.33, $2.58
B) The best deal is 24 cupcakes for $56
Step-by-step explanation:

Integrating both sides, we get


When

, we have

, so that

When

, we have

, which means