The red tail flew 8 meters a second
the formula for velocity is:
v= distance/time
distance= 80m
time=2 seconds
v=80/2
v=40ms-1
Answer:
A) False
B) False
C) True
D) True
E) True
Explanation:
A) The formula for tangential speed v in term of angular speed ω and radius of rotation r is

So if the angular speed is constant and 0, the tangential speed is also 0. A) is false
B) False because of the centripetal acceleration:

C) True because of the formula for tangential acceleration in term of angular acceleration α is

D) True because same as D), if it has angular acceleration, it would have a tangential acceleration. Also from B) the centripetal acceleration will come with time as soon as angular speed is generated by angular acceleration.
E) True and same explanation as from B)
The answer is hydrogen and helium
hope this helped (: