The answer is b) false. Stars are mainly classified by their spectra (the elements they absorb) and their temperature.
Answer:
The photoelectric effect is a phenomenon in which the photoelectrons are emitted from the metal when an incident electromagnetic wave hits the metal. The incident light should have a threshold frequency to meet the work function of the metal
Without friction, the amount of work only depends on the final height,
and is not affected by the route used to get there.
If the ramp has no friction, then it has no effect on the total amount
of work done. The work to lift the load straight up is the same.
If the ramp has some friction, then it takes more work to use the ramp
than to lift the load straight up. Then the work to lift the load straight up
would be less than when the ramp is used.
B- the biosphere needs the hydrosphere (water) to survive. They drink the water.
C- the biosphere use the géosphère as land/ home.
D-The géosphère depends on the hydrosphere for water. Without the water, the géosphère would eventually turn dry and nothing will be able to grow
E- The animals in the hydrosphere need air to survive. The gills on sea animals are used to filter out the water from the oxygen and use the oxygen to breathe. As the fish opens its mouth, water runs over the gills, and blood in the capillaries picks up oxygen that's dissolved in the water.