The car's final velocity is 11.6 m/s in the opposite direction.
Answer:
Intensity at 45 cm will be 0.2283 volt
Explanation:
We have given that intensity of signal measured by the detector is 0.74 volt at a distance of 25 cm
We know that intensity of signal is given by
, here s is strength of light and r is distance
So 

In second case
Intensity is given by 
So 
The material that the snails are moving on affects their speed. On a smooth material, (petri dish) the snails moved the fastest. On a rough material (sandpaper) the snails moved the slowest. On dirt, a compromise between smooth and rough, the snails moved at a medium pace. The material and possibly friction affect this.
No light does not need medium to travel.Its an electromagnetic(EM) wave.All EM waves travel independent of medium. In contrast mechanical waves need a medium,sound waves,shock waves are mechanical and they need medium to transfer energy or travel.
Me and you! enjoy your day girllllaa or boy