Write an expression to represent a circle's area in terms of its diameter, d .

(d/2)^2 pi

Step-by-step explanation:

To find the area of a circle the formula is A=pi times radius sqaured. Since we do not have the radius we need to find it. The radius will always be half the diameter hence the (d/2). This will give us the radius, next is just to complete the area formula by squaring the radius and multiplying it by pi.  i hope this helps :)

$4034.40

the perimeter of the field is the sum of the lengths of the four sides:

47 yd + 158 yd + 47 yd + 158 yd = 410 yd

the cost of 3 ft (1 yd) of fence is 3×$3.28 = $9.84.

so the cost of jake's wood perimeter fance is

(410 yd) × ($9.84 /yd) = $4034.40