You’re answer to this question would beD
Answer:
It has gotten worse.
Explanation:
In the past 30 years, air quality in the United States has declined almost exponentially. Pollution is the main reason for the declination of air quality in the United States, but there are different kinds of pollution, including light pollution, noise pollution, air pollution, water pollution, etc. Air pollution can be caused by primary or secondary pollutants. Primary pollutants include carbon, nitrogen, and sulfur oxides as well as just general particles in the air. Secondary pollutants are formed when pollutants are exposed to sunlight via chemical reactions.
Answer:
Chromosomes become visible, crossing-over occurs, the nucleolus disappears, the meiotic spindle forms, and the nuclear envelope disappears.
Explanation:
The duplicated homologous chromosomes pair, and crossing-over (the physical exchange of chromosome parts) occurs.
Answer:
reproduction
Explanation:
the male and female reproductive parts