20. a child has type a blood. what are all the possible blood types of its parents?
show each cross to prove that it is possible.

Two parents with A blood type can produce a child with either A or O blood types. ... If one parent has A and another has AB, they can either produce a child with A, B or AB blood types. If one parent has A and another has O, they can either produce a child with A or O blood types.

poor water quality affects most estuarine organisms, including commercially important fish and shellfish. the pollutants that have the greatest impact on the health of estuaries include toxic substances like chemicals and heavy metals, nutrient pollution (or eutrophication), and pathogens such as bacteria or viruses.

and i oop

explanation: