The heart has 2 chambers: The UPPER CHAMBERS are called the <u>atrium</u> and the LOWER CHAMBERS are called the <u>ventricles</u>
Therefore , answer is c
Answer:C
Explanation: Because the oldest fossils are in deeper layers
Scientists can calculate the number of neutrons by subtracting the atomic number from the atomic mass.
they subtract the protons
In the north Atlantic the movement of tectonic plates(if that is what you meant by plates) is around.4 inches per year which is almost 1 cm but in the pacific area the movement is almost 2 inches which is more that four cm every year although some people say that they (in general not specific to any place in particular) travel in the range of 5-10 centimeters every year.