Answer:
The correct answer is -
Independent Variable: change of speed
Dependent Variable: time takes to stop
Controlled Variables: stop at a stop sign
Explanation:
To know the effect of the speed to take the time to stop at a stop sign Bobbye perform this exercise where he changes the speed at each time that he is driving to know the time it takes to stop at a stop sign. There is a change that takes place purposely is in the speed of driving so it is an independent variable as the independent variable is a variable that is manipulated in an experiment or investigation.
The time it takes to stop is the factor that depends on the speed so it is the dependent variable as the dependent variable is the variable that depends on the independent variable.
The control variable remains the same or constant in an investigation which is stoping at a stop time irrespective of speed.
