The correct answer is D.
Echo refers to the sound that is heard when a sound wave is reflected back from a surface. An echo sound is made when a sound wave traveled through the air, hit a hard surface and get reflected back. Generally, hard surfaces reflect sound wave while soft surfaces absorb sound waves. Reflected sound waves are used in application of some devices that are used in range and direction finding.
Answer:
Explanation:
It is malleable, ductile, and a good conductor of electricity and heat.
The order of the answers are as follows:
B
C
D
A
Mass<span> is the amount of matter in an object. Move to a different planet and an object's weight will change, but its </span>mass<span> will be the same. </span>