By <span> It is directly proportional to the </span>average kinetic energy<span>.</span>
1.15 m/s to the left (3 sig. fig.).
<h3>Explanation</h3>
Momentum is conserved between the two balls if they are not in contact with any other object. In other words,

, where
stands for mass and
stands for velocity, which can take negative values.
Let the velocity of objects moving to the right be positive.
,
.
Before the two balls collide:
,
.
After the two balls collide:
needs to be found,
.
Again,
,
.
.
is negative? Don't panic. Recall that velocities to the right is considered positive. Accordingly, negative velocities are directed to the left.
Hence, ball A will be travelling to the left at 1.15 m/s (3 sig. fig. as in the question) after the collision.
Answer:
Convert all the times to either hours or seconds
Explanation:
One time unit is in hours, and the other is in seconds. In order to do the math, the units need to be the same. So you either need to convert hours to seconds, or seconds to hours.