Answer:
This is because there is no air in space – it is a vacuum. Sound waves cannot travel through a vacuum. ... Even the emptiest parts of space contain at least a few hundred atoms or molecules per cubic metre. Space is also filled with many forms of radiation that are dangerous to astronauts.
Their mass because it can let you know their weight and size
D : the number of generations in one population
The question is; would a drug that binds irreversibly to these receptors be an effective contraceptive in mammals?, the answer is;Yes; because if the receptors are blocked the sperms will not be able to penetrate the zonal pellucida of the egg. Contraceptives prevents pregnancy by interfering with the normal process of ovulation, fertilization, and implantation.
Carbon dioxide goes into the atmosphere and is absorbed by plants along with water, to produce oxygen an plant structures, whether cellulose, starch, or sugar-which are then eaten by mammals.
Stresses on the Earth's system include incomplete combustion of carbon to produce carbon monoxide. The burning of fossil fuels such as oil and carbon, And also the presence of excess ozone in the upper atmosphere.