Answer:Stars are formed in clouds of gas and dust, known as nebulae. Nuclear reactions at the centre (or core) of stars provides enough energy to make them shine brightly for many years. The exact lifetime of a star depends very much on its size.
Answer:
Los gases que tienen huellas de carbono son dióxido de carbono, monóxido de carbono y gases de metano, etc.
Explicación:
Los gases contaminados que contienen huellas de carbono son dióxido de carbono, monóxido de carbono y metano, etc. Estos gases tienen un efecto negativo sobre el medio ambiente porque son responsables del calentamiento global de la atmósfera y disminuyen la calidad del aire que produce muchas enfermedades nocivas. Las principales causas de la emisión de gases contaminados son las actividades humanas como la quema de combustibles fósiles y el humo que producen las industrias, etc.
Answer:
The “recommended temperature limit” indicates limit of the temperature that is good for our world.
Explanation:
The temperature related to the “recommended temperature limit” means that in the graph there is a limit of temperature for our world's environment. if the temperature is between this limit, there is less or no adverse effect on our environment while on the hand, if the temperature exceeds from this limit, then it adversely affected our world because the concentration of carbondioxide gas in the atmosphere increases due to this increase temperature..
Diploid sporophytic generation alternating with haploid gametophytic generation <span>phrases characterizes alternation of generation in algae.</span>
