D, it is considered unethical today
Answer:
This question is about matching each definition with its correct term. Please find the term matched with their appropriate definition below.
Explanation:
1. Empirical evidence: An empirical evidence is an observational evidence i.e an evidence gathered by observation or use of senses.
2. Dependent variable: Dependent variable is an experimental factor that changes in response to a change in the independent variable. In other words, it is dependent on the independent variable.
3. Applied research: Applied research is a type of research oriented at solving a present problem or need. It encompasses the production of products that can be sold for profit.
4. Hypothesis: A hypothesis in an experiment is a proposed explanation for a scientific problem that itself can be tested by experimentation. A hypothesis aims at providing a testable explanation to an observed problem.
5. Control: A control is a quantity in an experiment that remains unchanged or constant. It is kept the same by the experimenter for all groups in the experiment in order not to influence the outcome.
6. Basic research: Basic research is the research that expands knowledge in a particular area. It is the kind of research that aims at filling a knowledge void or satiating curiosity.
7. Independent variable: The independent variable is the experimental factor that is changed or manipulated deliberately by the scientist.
Answer:
The average force exerted on the window due to two snowballs is 6 N
Explanation:
Given:
Mass of snowballs 
Kg
Velocity of snowball 
For finding the average force,
Force is equal to the change in momentum,
Here, final velocity is zero so we write,
Where 
sec
N
Above value of force is due to one ball, but here given in question there are two ball,
N
Therefore, the average force exerted on the window due to two snowballs is 6 N
Answer:
A fired bullet
Explanation:
A fired bullet is faster than the speed of sound
