Answer:
Sound waves transfer energy by causing successive compressions and rarefactions in the particles of the medium without transporting the medium particles themselves. Sound in solids can also manifest as transverse waves, causing crests and troughs in the propagation medium.
Answer:
Option e) 320 s
Explanation:
Here, distance = 3.0 km = 3000 m
The velocity of boat when it is going upstream;
Upstream velocity = velocity of boat in still water - velocity of river flow
So, Upstream velocity 
So,Time to go upstream

The velocity of boat when it is going downstream;
Downstream velocity = velocity of boat in still water + velocity of river flow
So, Downstream velocity 
So,Time to go downstream

So, total time (t) = 
Option E is the correct answer.
Using the precise speed of light in a vacuum (

), and your given distance of

, we can convert and cancel units to find the answer. The distance in m, using

, is

. Next, for the speed of light, we convert from s to min, using

, so we divide the speed of light by 60. Finally, dividing the distance between the Sun and Venus by the speed of light in km per min, we find that it is
6.405 min.
Please provide the choices to select the possible choices.