Question

a company wants to test the effectiveness of a new ethanol based fuel. they fill a kia soul completely with standard gasoline. with the old fuel in the car, they drive at 20 mph until they run out of gas. they measure how many miles they are able to drive without filling up. they then fill the kia soul with the new ethanol based fuel and repeat the process.\
\bigcirc independent variable\
\bigcirc dependent variable\
\bigcirc constant\
\bigcirc control variable\
\
which is an example of a low income country? *\
\bigcirc chile\
\bigcirc russia\
\bigcirc india\
\bigcirc uganda\
\bigcirc united states

Explanation:

First Question (Variable Type in Experiment)

In the experiment, the car model (Kia Soul), speed (20 mph), and process of driving until running out of gas then refilling are kept the same. A control variable is a factor held constant to prevent it from influencing the experiment's outcome, helping to isolate the effect of the independent variable (fuel type). Here, these constant factors are control variables. The independent variable is the fuel type (old vs new), dependent is miles driven, and constant isn't the right term here as control variable refers to held - constant factors in an experiment.

Low - income countries typically have lower GDP per capita, less industrialization, and higher poverty rates. Uganda is classified as a low - income country. Chile is a high - income country, Russia is an upper - middle - income country, India is a lower - middle - income country, and the United States is a high - income country.

Answer:

D. Control Variable

Second Question (Low - Income Country)