To assess whether intelligence is a single trait or a collection of several distinct abilities, psychologists have made extensive use of?

factor analysis

Explanation:

Factor analysis is a form of statistical technique through which one identifies factors ( groups or clusters) during a test. It is used to explain the correlation among a group of test scores. It is used to determine whether questions on a survey reflect broader underlying dimensions called factors, ideally independent of each other.

add the answer choices and i'll give you the answer

two jet streams that directly affect the formation of weather in the continental part are a polar jet and a subtropical jet. they are responsible for the transportation of weather systems, which directly affect people. the polar front is the boundary between cold air from the north pole and warmer equatorial air. both the polar jet and the subtropical jet blow from the west to the east, and follow the boundary between cold and warm air.

the strongest jet streams are polar jets, while subtropical jets are somewhat weaker.

the right answer is c. the polar jet stream is generaly stronger than the subtropical jet stream.