Answer to Question 1
D
Answer to Question 2
It is possible to demonstrate a relationship between two variables by simply observing them. However, simple observation cannot establish the direction of the relationship. For example, you may observe that two variables change together consistently: as variable A increases, variable B also increases. However, you cannot determine whether changes in A are causing changes in B, or whether changes in B are causing changes in A. To avoid this problem in an experiment, the researcher takes charge and manipulates one of the variables. For example, the researcher increases the value of variable A and then observes variable B to see if it is affected by the increase. If B also increases, then the researcher can conclude that changing variable A has caused changes in variable B.
The direction of plant cell expansion is controlled by microfibrils and microtubules. Plant cells en
Rutherford Scattering Experiment
The notorious standford prison experiment
The swan neck flask experiment
Controlled cold compression unit.
A typical variable cam timing control valve. The solenoid is controlled by the engine computer and ...