Answer:
independent quantitative.
Step-by-step explanation:
An indepentent variable in an investigation, is the variable that will be changed in order to know how its variation affects the dependent variable.
In this case, the dependent variable is the test scores since Dr Washington will study there is the numeber of hours of study affects the grade the students obtain.
Therefore, the hours of study are the independent variable.
It is also a quantitative variable since it can be counted.