Which of the following is true of experimental data?

a. Experimental data is sometimes called retrospective data.
b. Experimental data cannot be collected in a controlled environment.
c. Experimental data is sometimes called observational data.
d. Experimental data are collected in laboratory environments in the natural sciences.

changes in factors like average income and preferences can cause an entire demand curve to shift right or left. this causes a higher or lower quantity to be demanded at a given price. demand curves relate the prices and quantities demanded assuming no other factors change. it is important for consumers to know this information, because it is crucial for them to know what they can afford and can't afford. i hope this .

not  

cuba  

russia  

iraq  

el salvador  

explanation:

known as the land of volcanoes, el salvador has visit seismic tremors and volcanic movement. it is the main nation in central america that does not have a coastline on the caribbean sea. about portion of all salvadorans live in the wide open. they are poor and don't have power or running water in their homes. in 1525, pedro de alvarado, a lieutenant of cortés's, vanquished el salvador. el salvador, with alternate nations of central america, pronounced its freedom from spain on sept. 15, 1821, and was a piece of a league of central american states until the point when that association broke up in 1838.

answer; the miracles;

answer; which categories of people are most at risk of becoming a criminals;