D lowering the activation energy of a reaction.
Answer:
Physical Weathering
Explanation:
As per the given conditions in the question, the primary effect is <u>mechanical action</u> which is also known as a <u>physical weathering</u>. During mechanical action, a rock is disintegrated into the smaller pieces. In the given statement, <u>the root of tree would grow in the crack and try to develop a strong network to get nutrients necessary for tha tree growth</u>. Thus, the <u>root would exert a pressure</u> in the crack to make more space for its growth and development (root network). This is primarily a mechanical action and an example of physical weathering.
Answer:
The answer includes all of the options.
Explanation:
Some of the major changes that happened in agriculture during the 1920s include the use of electrical tools and vehicles and chemical fertilizers. These changes along with their low availability to the average farmers made it harder for them to compete with agricultural corporations who could use these advanced methods easily. Hybrid seeds were also used by corporations to get increase the yield of the fields. The answer includes all of the options.
I hope this answer helps.
Carbon can form up to 4 covalent bonds