The measure of an arc is the measure of its central angle, which is indicated as
Answer: 90°
right there in the figure.
Answer:

Step-by-step explanation:
Since Θ is in fourth quadrant then cosΘ > 0, as is secΘ
Given
sinΘ = -
, then
cosΘ = 
=
=
= 
Hence
secΘ =
= 
Answer: 1/35
Step-by-step explanation:
1/5 = 0.2
0.2/7= 1/35
Answer:
∠ BCA = 45°, ∠ AWD = 90°
Step-by-step explanation:
All angles are right angles by definition.
Diagonals bisect the angles , so
∠ BCA = 45°
Diagonals are perpendicular bisectors of each other, so
∠ AWD = 90°