How does the body differentiate between potential pathogen and the body’s cells?

Ascientist and her team counted 200 individual deer in an area of 10 square kilometers. what is the population density?

Four different thermometers were used to measure the temperature of a sample of pure boiling water. the measurements are recorded in the table below. thermometer temperature reading 1 temperature reading 2 temperature reading 3 w 100.1°c 99.9°c 96.9°c x 100.4°c 102.3°c 101.4°c y 90.0°c 95.2°c 98.6°c z 90.8°c 90.6°c 90.7°c the actual boiling point of pure water is 100.0°c. what can be concluded from the data about the reliability and validity of the thermometers?

What were the main components of earth’s earliest atmosphere? oxygen and ammonia hydrogen and helium oxygen and nitrogen hydrogen and nitrogen