Answer:
b. energy loss in machines
Explanation:
It is an undesirable effect because it causes loss in energy in a machine which most likely requires a lot of energy to function. Therefore, it is undesirable as the machine will not function properly.
It's likely to have a Solid Grey color.
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.