Answer:
C=$(4.30xy+5.40(xz+yz))
Step-by-step explanation:
Surface Area of a Cuboid=2(LW+LH+HW)
Since the top is open
Surface Area = LW+2(LH+HW)
If Length = x feet,
Width =y feet
Height = z feet
Surface Area = xy+2(xz+yz)
Area of the base=xy
If it costs $4.30 per square foot to build the base
Cost of the base=Cost Per Square Foot X Area = $4.30xy
Area of the sides =2(xz+yz)
If it costs $2.70 per square foot to build the sides
Cost of the sides=Cost Per Square Foot X Area of the sides
= 2.70 X 2(xz+yz)
=5.40(xz+yz)
Cost of Constructing the Box = Cost of Constructing the Base + Cost of Constructing the Sides.
Therefore,
C=$(4.30xy+5.40(xz+yz))
It would be the first answer. Bubble. I don't know what you call it. But yeah, it's the first one.
This statement will be
false. -7+9=2
-9+7=-2

, therefore, this statement is false.
X^2
diff. w.r. to x
=dx^2/dx
=2x^(2-1)
=2x .....