Answer:
B
x is the price of the sweater so 3x and add $15 for the skirt which would add up to $90
Answer:
True, see proof below.
Step-by-step explanation:
Remember two theorems about continuity:
- If f is differentiable at the point p, then f is continuous at p. This also applies to intervals instead of points.
- (Bolzano) If f is continuous in an interval [a,b] and there exists x,y∈[a,b] such that f(x)<0<f(y), then there exists some c∈[a,b] such that f(c)=0.
If f is differentiable in [0,4], then f is continuous in [0,4] (by 1). Now, f(0)=-1<0 and f(4)=3>0. Thus, we have the inequality f(0)<0<f(4). By Bolzano's theorem, there exists some c∈[0,4] such that f(c)=0.

The answer is above.
Additional note 1:

Additional note 2:
In the answer I filled in "0" at the place where "n" was. This is because the question tells us n=0
First if there are 47/80 we have to estimate like 47 is 50 and 82 is 80
Add the bases together, divide that by 2 then multiply by the height.
15.8 + 21.8 = 37.6
37.6/2 = 18.8
18.8 x 11.7 = 219.96 yd^2