A trace gas is a gas which makes up less than 1% by volume of the Earth's atmosphere, and it includes all gases except nitrogen (78.1%) and oxygen (20.9%). The most abundant trace gas at 0.934% is argon.
Answer:
The acceleration of Abbie is half of the Zak's.
Explanation:
The centripetal acceleration of an object on a circular path is given by :

Two children are riding on a merry-go-round that is rotating with a constant angular speed. Let
is distance of Abbie from the merry-go-round and
is distance of Zak's from the merry-go-round. Acceleration of Abbie is :
...... (1)

Acceleration of Zak's is :
.......(2)

Dividing equation (1) and (2) we get :

So, the acceleration of Abbie is half of the Zak's.