Some factors could be:
weather
ressources
Population density =number of individual divided land area
land area should be in square kilometers
therefore 120 ha =120 x0.01=1.2 square kilometer since 1 ha=0.01 kilometer square
total population= (80 x 1500)/100=1200
population density is therefore=1200/1.2=1000
A baby's immune system is not fully developed until he/she is about six months-old. In the meantime, pregnant mothers pass immunoglobulin antibodies from their bloodstream, through the placenta, and to the fetus. These antibodies are an essential part of the fetus's immune system. They identify and bind to harmful substances, such as bacteria, viruses, and fungi that enter the body. This triggers other immune cells to destroy the foreign substance.
Answer:
A mass
Explanation:
I learned it in 8th grade.
