Answer:
the second option!
Step-by-step explanation:
hope this helps! will appreciate brainliest!
Answer:
6.6 cm and 14.6 cm
Step-by-step explanation:
(a)
the length of arc AB is calculated as
AB = circumference of circle × fraction of circle
= 2πr × 
= 2π × 4 × 
= 8π × 
= 
≈ 6.6 cm ( to the nearest tenth )
(b)
the perimeter (P) of sector AOB is
P = r + r + AB = 4 + 4 + 6.6 = 14.6 cm
A)

_________________________________
B)

Or

_________________________________
C)

Answer:
-1/root2
Step-by-step explanation:
7pi/4 radians is the same as -pi/4 radians
sin(-pi/4) is -sin(pi/4) = -1/root2