Answer:
Option (D)
Explanation:
In terms of chemistry, a catalyst is usually defined as the substance that is commonly used in a reaction in order to increase the rate of reaction, without getting consumed. It helps in the reduction of activation energy.
In the given case, the lever or a person can be considered as a catalyst because both of these will increase the efficiency (or rate) in removing the rock from the top of the perch. Thus, the lever or the human will remain the same after the removal of rock as a catalyst can be recovered after the reaction.
Therefore, the correct answer is option (D).
Answer:
increasing soil erosion.
Explanation:
Mining for mineral resources is an intensive task that involves disturbing and disrupting the lands where the minerals are found. The process of mineral exploration and eventual mining cause great disturbances to the affected land and one of the damages done to such land is great increase in soil erosion.
Option A
DNA is always synthesized in the 5' to 3' direction, meaning that nucleotides are added only to the 3' end of the growing strand.
Trilobites are found worldwide and evolved rapidly, making them easily distinguishable from trilobites of other time periods