if the color changes, it is neutral but if it stays the same, it is an acid.
Solution :
Given
Diameter of the roulette ball = 30 cm
The speed ball spun at the beginning = 150 rpm
The speed of the ball during a period of 5 seconds = 60 rpm
Therefore, change of speed in 5 seconds = 150 - 60
= 90 rpm
Therefore,
90 revolutions in 1 minute
or In 1 minute the ball revolves 90 times
i.e. 1 min = 90 rev
60 sec = 90 rev
1 sec = 90/ 60 rec
5 sec = 
= 75 rev
Therefore, the ball made 75 revolutions during the 5 seconds.
The correct answer is D: Watt. This unit was named after James Watt, and
is used to express the equivalent of one joule per second in energy. In
experiments and on the packaging for electrical products such as light-bulbs, the measurement will usually be written in its abbreviated
format: W.
<span />
Acceleration occurs when velocities change.velocity changes either because the speed changes or the direction change.
Answer: D
The final velocity of the object will be directed north of east
Explanation: