What receives blood from the head

Chicken pox and hepatitis are bacterial diseases. true or false?

Apopulation of black bears depends on salmon from a stream for food. if a drought causes the stream to run dry one year, how will this likely impact the black bear population?

There are two tomato plantlets one of them is kept in an oxygen chamber with a light source and another is kept in sunlight. both of them are watered regularly what will be the observation after two weeks