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).
Resultant force = mass × acceleration, therefore acceleration = resultant force ÷ mass
Resultant force = 19 - 1.7 = 17.3 N
acceleration = 17.3÷2= 8.65 ms-2
Carbohydrates such as glucose, cellulose, deoxyribose, fructose, etc
Nucleic acids such as DNA, mRNA, tRNA
Proteins such as structural proteins and enzymes
You didn't put any answer choices, but air and water are generally the greatest.
