Answer:
yes
Explanation:
All parts of the body (muscles, brain, heart, and liver) need energy to work. This energy comes from the food we eat. Our bodies digest the food we eat by mixing it with fluids (acids and enzymes) in the stomach.
energy extracted out of liquids an atoms are left to come closer arrange themselves shorter distance and then they solidify
Here since both children and merry go round is our system and there is no torque acting on this system
So we will use angular momentum conservation in this

now here we have



Now when children come to the position of half radius
then we will have



now from above equation we have


Answer:
YES
Explanation:
An echo may be defined as a sound which is repeated because of the sound waves that are produced are reflected back after striking a surface. Sound waves can smoothly bounce off the hard objects in the same manner as a rubber ball bounces back the ground.
When a sound wave strikes a hard surface, the sound waves gets reflected back and bounces back to the observer and produces an echo. If the sound waves strikes a soft surface it absorbs the sound.
Although the direction of a sound changes but the echo sounds in the same way as the original sound.