A contractor is to build a warehouse whose rectangular floor will have an area of 4000 square feet. The warehouse will be separated into two rectangular rooms by an interior wall. The cost of the exterior walls is $175 per linear foot and the cost of the interior wall is $125 per linear foot. Express the contractor's cost for building the walls, C, as a function of one of the dimensions of the warehouse's rectangular floor, x.

C(x)= 475x + (1400000/x)

Step-by-step explanation:

Let length be x

Let width be y

Let area be A

A= xy

Xy=4000

y=4000/x

Interior wall length/ x

Total cost = 125x

Exterior wall length = perimeter of rectangle floor=2(x+y)

Total cost == 175×2(x+y)=350(x+y)

Contractors cost

C(x)= 125x + 350(x+y)

C(x)= 125x +350x +350y

C(x) = 475x + 350(4000/x)

C(x) = 475x +(1400000/x)

a) one student is chosen from classroom a, then a student is chosen from classroom b.  

step-by-step explanation:

independent events are ones in which the probability of one event does not affect the probability of the second event.

one student is chosen from classroom a; this does not affect the chances of choosing a student from classroom b.   this makes these independent events.

when one card is chosen from a standard deck and then set aside before a second card is chosen, the probability of the second card being chosen changes.   this makes them dependent events.

when one student is chosen from classroom a and then a second student is chosen from classroom a, the probability of choosing the second student changes.   this makes them dependent events.

when a letter is chosen from the alphabet and then a second letter is chosen, the probability of choosing the second letter changes.   this makes them dependent events.