Answer:
Sound waves are reflected back
Use round wheels to roll the heap, help the weight by evacuating appended or contained protests, or place a smoother surface betwen the question and the floor. Water or different liquids can be utilized to diminish the protection, yet just on the off chance that they stay between the question and the floor.
The needle on a compass always points in the direction of magnetic north because of the magnetic poles of earth. the compass is essentially a magnet itself, so the southern pole of the compass is attracted to the northern pole of earth.
Have wavelengths that are longer than normal.
