A. the carbons are unbalanced
B. the hydrogens are unbalanced.
D. the chlorines are unbalanced.
That leaves C. to be correctly balanced.
It appears to be a <span>spiral shape. </span>
D ....Do you remember your teacher going over different physical and chemical reactions....It is a chemical reaction because it will never go back to the previous state...therefore your correct and it is a chemical reaction.
This problems a perfect application for this acceleration formula:
Distance = (1/2) (acceleration) (time)² .
During the speeding-up half: 1,600 meters = (1/2) (1.3 m/s²) T²
During the slowing-down half: 1,600 meters = (1/2) (1.3 m/s²) T²
Pick either half, and divide each side by 0.65 m/s²:
T² = (1600 m) / (0.65 m/s²)
T = square root of (1600 / 0.65) seconds
Time for the total trip between the stations is double that time.
T = 2 √(1600/0.65) = <em>99.2 seconds</em> (rounded)
