Answer:
Animal ; prokaryote ; plant ; virus
Explanation:
Animal: An animal cell possesses cell membrane, ribosomes, lysosomes and nuclear membrane.
Prokaryote: In a prokaryotic cell, cell wall is present such as bacteria, ribosomes are present but nuclear membrane is absent
Plant: A plant cell possesses cell wall, ribosomes, nucleus and a large vacuole.
Virus: Viruses reproduces inside a cell because they do not have their own energy producing system, nucleus is absent but nucleic acid ( DNA or RNA) is present
The correct answer is: The speed of sound is faster in the water than in the air.
The speed of sound is different between those two mediums because they have different densities. Since, water is denser than air, more energy is required to generate a wave but once it stars, it travels faster than it would do in air. Sound waves’ travel can be presented by particles that transmit the energy one to another as they bump. The sound speed is lower in the air (than in water) because particles are far apart, so they travel further before they collide.
Answer:
Volume= 4 cm³
Density= 2 g/cm³
Explanation:
We have the following data:
volume= V= 8 cm³
mass= m= 16 g
The density is the mass per volume of a substance, so the density of the rock is:
density= d= 16 g/8 cm³= 2 g/cm³
When we cut the rock in half, we have a half volume and a half mass:
V= 8 cm³/2= 4 cm³
m= 16 g/2= 8 g
But the density is not altered because it is an intrisic property - it does not change with the amount of subtance. Thus, the density of a half rock is:
d = m/V= 8 g/4 cm³= 2 g/cm³
