Why would you not expect to find live plants or photosynthetic plankton in the deep-water zone of a lake?

Does anyone know the answers for questions 1-4? plz me out if you know

The united states economy is one in which producers are generally free to produce what they want and consumers are free to purchase what they desire, so long as no laws are broken. at the same time, however, the government does regulate some aspects of the economy. the u.s. can best be described as which of the following a mixed economy b liberated economy c command economy d market economy

How is the uk’s government is solving the air pollution problem?