Answer
Correct answer is :It has two elements
Explanation
A binary compound is a compound that is made up of two of the elements in the periodic table. Some examples of binary compounds are 
and 
. This means that a binary compound can have more than 2 atoms as in the case of hydrogen oxide. Some binary compounds are ionic as in the case of sodium chloride.This shows that they do not necessarily have to have covalent bonds. This also rules out the possibility that they may always have double bonds as ionic compounds are bound together by ionic bonds. The only thing that will always be true of binary compounds is that they will always have 2 elements.
The horrific forced transport of Africans into America during the age of exploration as part of the slave trade that was going on where Africans were transported on ships from Africa, chained up like animals all the way to America was an example of international migration affecting the population.
External influences forced Africans to go from Africa to another continent and live there.
Blood type because looking at someone, you cannot determine their blood type.
Contraction of skeletal muscles against the lymph vessel
The lymph usually move in the body in its own vessel and travels from the interstitial spaces to the subclavian veins at the neck area. The lymphatic system does not have a heart to pump and move the fluid. The movement of lymph depends on the movements of the muscles and joints in the body. In this mechanism upward movement is possible. It will move towards the neck where it will be filtered and will go again into the subclavian veins.
