Answer:
a=21
b=69
c=42
d=138
Step-by-step explanation:
c is supplementary to d (which is 138), so c=180-138= 42.
angle b is on the edge of the central angle 138, so b is 1/2, therefore, b=69.
angle a is complementary to angle b because any triangle that includes the diameter is a right angle, so angle a=90-69=21.
D
Area of a circle is: 兀r✖️r, so 4.1m ➗2 = 2.05, 2.05✖️2.05 = 4.2025
Answer:
Its addition I think so the answer would we 16.7399km for both trials
Step-by-step explanation: