The answer is either
b A system in which Newton's Laws are valid
or
c A system in which there are no external forces.
Explanation:
not a, and not d
There are energy changes in a closed system.
A closed system obeys the conservation laws in its physical description.
Answer:
reflection of water ,sound and water waves etc
Answer: ice float in water due to density differences. Water has a higher density than ice.less dense object in liquid with high density
Explanation: from density formulae.
D=M/V
Density of ice =Mass of ice/Volume of ice
D=23/25
D=0.92g/cm^3