o investigate the effects of exercise on mathematical problem-solving ability, a researcher assigned subjects to one of two groups. One group did 50 jumping jacks, the other group did 200 jumping jacks. After exercising, both groups did a set of math problems and their performances were compared. In this experiment the number of jumping jacks is the variable.

Independent

Explanation:

The independent variable in an experiment is the one that is not dependent on the other variable being measured. It is the variable that is manipulated such that the groups being experimented on get varying amounts of it so that their effect on dependent variable can be seen.

In this scenario, the mathematical problem-solving ability is being investigated to see if it depends on the number of Jumping jacks done and so the 2  groups were given a different number of jumps to do. Jumping jacks are therefore the independent variable.

the factors that the economies of the muslim empires prosper were:

1- land trade routes-located between three continents  

2- sea trade routes

trade contributed to the spread of muslim empires, and with that islamic culture led to a growing feeling of internationalism resulted in the transfer of technology, science, and other cultural forms.

answer; lewis henry morgan;