Primary treatment in a sewage treatment plant is
a. using microorganisms to treat the water
b. returning the water to a river
c. using chemicals to treat the water
d. removing solids from the water

Primary treatment in a sewage treatment plant is
removing solids from the water

The virus is considered to be are living item since they have hereditary material dnas or rnas. they can imitate and change. they respond to boosts, for example, radiation, chemicals, and warmth. they have antigenic properties. they are proficient to duplicate with a same hereditary constituent.