How many chambers does the heart contain?
a. 3
b. 4
c. 5
d. 6

The best answer is b.  4

The human heart has  four chambers - two atria and two ventricles.

1. Right atrium -  receives oxygen-poor blood from the body and pumps it to the right ventricle.

2. Right ventricle -  pumps oxygen-poor blood to the heart.

3. Left atrium - receive oxygen - rich blood from the  lungs.

4. Left ventricle - pumps oxygen rich blood to the body.

The heart is a muscular organ. It is about the size of a closed fist. It is located in the thoracic cavity. It is protected by the rib cage and is the major organ of the circulatory system.

the "power" of a lens is its resolution power, or its ability to distinguish between to closely located points. with the low power lens, it is likely you will see the rough form of the hay and maybe some movement of dots around the hay. however, when observed with the high power lens, the detailed features of the hay become visible and the microbes being grown are more clearly visible.

i hope this you