Answer:
Explanatory variable: Extra support by faculties
Response variable: whether community college students who have assess into elementary algebra could be successful if they were placed directly into college-level statistics.
Confounding Variable: Ability of students to get passing grades.
It is an experiment to check if the hypothesis is true.
Step-by-step explanation:
An explanatory variable is a type of independent variable. An explanatory variable is that variable that explains changes in another variable. It can be anything that might affect the response variable. The explanatory variable is used to predict or explain differences in the response variable. In an experimental or research study, the explanatory variable is the variable that is manipulated by the researcher.
From the information given,
Explanatory variable: Extra support by faculties.
The response variable is also known as the dependent/outcome variable. Here, its value can be predicted or its variation can be explained by the explanatory variable. In an experimental study, this is the outcome that is measured after manipulation of the explanatory variable
From the question above,
Response variable: whether community college students who have assess into elementary algebra could be successful if they were placed directly into college-level statistics.
A confounding variable is that outside influence that changes the effect of a dependent and independent variable. This extraneous influence is often used to influence the outcome of an experimental design. The Confounding Variable in the above is:
Confounding Variable: Ability of students to get passing grades.
It is an experiment to check if the hypothesis is true.
and 
, respectively. The total probability of knocking down at most two is thus 
, or 
.