Recall, The arc length [s] of a section of a circle is equal to the circles radius [r] times the central angle [theta] that the arc subtends. in radians.

r = 2.5 m.
s = 3 m.

Answer:
x = 60.
Step-by-step explanation:
Vertical angles are congruent so
x + 20 = 80
x = 80 - 20 = 60.
Answer:
a. range: 4
b. 5 students
c. mean: 8
Step-by-step explanation:
range: subtract the smallest number from the largest number in the data.
10 - 6 = 4
students amount was counted by the number of marks given.
mean: add the data together. (40) divide the sum by the number of marks provided. (5)
40 divided by 5 equals 8
I hope this helps. good luck