APPARENT MOTION- <span>the sensation of seeing movement when nothing actually moves in the environment, as when two neighbouring lights are switched on and off in rapid <span>succession.</span></span>
<span>So the question is what gases form the atmosphere of Uranus. So Uranus and Neptune are classified as "ice giants". They have a similar atmosphere to "gas giants" Saturn and jupiter and Neptunes atmosphere is primarily composed out of hidrogen and helyum. So the correct answer is a.</span>
Since there is no decimal point in the number given above, the counting for the number of the significant figures will start from the left. Then, the first zero from the left is insignificant. Therefore, in this number there are 6 significant figures.