Plane acb
plane bac
plane bca
plane cab
plane cba
Answer:
6.75
Step-by-step explanation:
h=hat, s=scarf
5h + 1s = $47 (equation 1)
2h + 2s = $40 (equation 2)
multiply equation 1 by 2 , we get: 10h + 2s = $94 (equation 3)
equation 3 minus equation 2, we get:
8h = $54 ⇒ h = $6.75 ⇔ 1 hat cost $6.75
substitute h = $6.75 into equation 2 to find s,
2($6.75) + 2s = $40
$13.5 + 2s = $40
2s = $26.5
s = $13.25 ⇔ 1 scarf cost $13.25
C=2πr
r=C/(2π), now the surface area is:
A=4πr^2, using r found above we have:
A=4πC^2/(4π^2)
A=C^2/π, we are given that C=28 so:
A=28^2/π in^2
A=784/π in^2
A≈250 in^2 (to nearest square inch)
