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.
They are good conductors of heat and electricity.
They are solid at room tempature
They have a high melting point
Yes ...................................
substance is matter of particular or definite chemical constitution ex: iron, methane
mixture are two or more substances that have been combined to retain their individual chemical characteristics ex: salt water, cola
Answer:
2510
Explanation:
Since there are 10 milimetres in 1 centimetre, 1 cm = 10mm
There are 10 times as many milimetres as centimetres.
251cm X 10 = mm
251cm = 2510mm
