To test the potential effect of hunger on taste sensitivity, groups of research participants are deprived of food for differing lengths of time before they engage in a taste-sensitivity test. This research is an example of

Experimental research

Explanation:

Experimental research is a scientific approach to research one or more independent variables are varied and applied to one or more dependent variables to measure the effect of the independent variable on the dependent variable. Experimental research is normally done when a relationship between variable (i.e independent and dependent) is needed to be determined. It includes a hypothesis, a variable that can be manipulated by the  researcher, and variables that can be measured, calculated and compared.

1. artillery

2. jose san martin

3.their economies remained dependent on outside powers.

4. drafted new economies

5. democracies have replaced dictatorships

your answer would b. the missisipi river

hope i you : )