There are several information's already given in the question. Based on those information's the answer can be easily deduced.
Distance traveled by the bicycle rider = 50 km
Time taken to travel the distance = 2.5 hours
So
In 2.5 hours the bicycle rider travels = 50 km
Then
In 1 hour the bicycle rider travels = 50/2.5
= 20 km
Then the average speed of the cyclist is 20 km per hour.
Answer:
D. The frequency is not affected as the volume of sound increases
Explanation:
Volume of the sound is defined by the amplitude of the wave or how loud a sound is whereas Frequency is basically the pitch of the sound and is inversely proportional to the wavelength . Increasing frequency will increase the pitch of the sound without affecting it's volume.
The shape of a liquid can change because the atoms in it are not close together to form a solid, they flow freely.
