The sources of air masses occur only in low and high latitudes because
group of answer choices
a. middle-latitude weather is too variable.
b. there is insufficient contrast in surface type (land vs. ocean) in the middle latitudes.
c. middle-latitude weather is not variable enough.
d. there are no oceans in the middle latitudes.

b. There is insufficient contrast in surface type (land vs. ocean) in the middle latitudes.

Explanation:

The sources of air masses can be produced or at very high latitudes because they can carry big amounts of air from the top of a mountain till the bottom by the differences of pressure and temperatures. This kind of air mass is called continental.

In the other hand, in a low latitude, the air coming from the sea, try to reach higher latitudes, again, by pressure and temperatures differences. These kind of air masses are called maritime.

Hope it was useful.

there's multiple reasons why the conquistadors were so successful in colonizing central america, and some of them are:

- they were seen as gods;

at the beginning, the spanish settlers were seen by the natives as gods, and this was mainly due to their white skin, and the way they came with their boats.

- possessed superior weaponry;

the spanish had gunpowder and guns, as well as cannons, while the natives did not had any fire weapons.

- made cleaver alliances;

they used the situation of tribes hating each other, so they made alliances with some of them which served them very well.

- brought diseases;

the native people were not immune to certain diseases the europeans brought with them, so they were dying from seeming harmless things for european standards.