If light moves at a speed of about 3.00 x 108 m/s, how long will it take light to travel the distance of a marathon (about 42.2 km)? express your answer in microseconds using the correct number of significant figures. do not enter your answer using scientific notation.

The time taken in microseconds equals 140.7 microseconds

Explanation:

From the basic relation of speed, distance and time we can write

In our case distance equals 42.2 kilometers which equals

Using the given values in the above relation we get

Converting into microseconds we get

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.

level 4 to level 2 : ))