There are a lot of human activities that gives negative effects on the earth's ecosystem but I will mention only four: Burning of things such as garbages or plants and trees, dumping of garbages anywhere, chemical substance that are being made and produced, cutting down of trees for replacement of buildings and homes. The human activities increase the occurrence of species extinction by doing this, it eliminates and destroy the homes of the species that are supposed to be living on their natural habitat. But instead of them, living peacefully, by doing these activities, their home will be destroyed that can kill them-- which can lead to extinction.
The flow of energy from one level to another does not happen with 100% efficiency. The producers only transfer 10% of the energy they absorb from the Sun. The major chunk of the absorbed energy goes into the growth of the producers, the rest gets lost in the form of waste (shedding of leaves, reproduction, etc.) and the remaining 10% is the amount that is available to the primary consumers. So by this logic, if there is 150,000 KJ of energy available at the producer level, then, only 15,000 KJ of energy will get transferred to the primary consumers.
some gets converted into sound energy and escapes into the surroundings.
hope it helps..!!!
Answer:
After 48 hours amount left = 6.25 g
Explanation:
Given data:
Half life of potassium = 12 hours
Total mass = 100 g
Mass left after 48 hours = ?
Solution:
Number of half lives passed:
Number of half lives = Time elapsed / half life
Number of half lives = 48 hours/ 12 hours
Number of half lives = 4
At time zero = 100 g
At first half life = 100 g/ 2 = 50 g
At 2nd half life = 50 g/2 = 25 g
At 3rd half life = 25 g/2 = 12.5g
At 4th half life = 12.5 g/2 = 6.25 g
