Well Zack's cost more because, he paid $567.00 for whatever he bought, while Mal paid $245.00 for whatever he bought.
Answer:
P is exactly 3km east from the oil refinery.
Step-by-step explanation:
Let's d be the distance in km from the oil refinery to point P. So the horizontal distance from P to the storage is 3 - d and the vertical distance is 2. Hence the diagonal distance is:

So the cost of laying pipe under water with this distance is

And the cost of laying pipe over land from the refinery to point P is 400000d. Hence the total cost:

We can find the minimum value of this by taking the 1st derivative and set it to 0

We can move the first term over to the right hand side and divide both sides by 400000


From here we can square up both sides






d = 3
So the cost of pipeline is minimum when P is exactly 3km east from the oil refinery.
Answer:

Step-by-step explanation:
Roots of the equation are -4 and -3.
Quadratic equation can be written as

The volume flow rate of the air being pumped into the football will be given by:
Q=V*A
Where
V=Speed
A=Area
You know that your pump expels air at speed of 8.2 ft/s
The area of The needle of your pump is
A=pi*r^2=pi*((4.5/1000)*(3.28))^2=0.00068442 ft^2
Finally
Q=V*A=(8.2 ft/s)*(0.00068442ft^2)=0.005612243 ft^3/s