Parent is the correct answer.
Lev Vygotsky was a Soviet psychologist whose main work was focused on developmental psychology and had the book "Pedagogical Psychology" published. <u>According to Vygotsky, a child's first guided participation is provided by a mentor who is most likely a parent.</u>
Since with have both the distance and the velocity of both cars, we can calculate their velocities, which is distance/time.
Roger:
2 miles in 7.5 minutes -> 
2 miles in 0,125h -> 
Natalie
2 miles in 6.5 minutes -> 
2 miles in 0,1083h -> 
With their velocities in hand you can draw your own conclusions ;)
There are two kinds of changes: physical and chemical. Physical properties can change without changing the substance, while chemical properties do change the substance.
Physical properties, like you said mass or texture, can change without changing the substance because the properties don't change the fundamental state of the subject; it doesn't change anything like atoms or molecules.
For example, when you freeze water to make ice, it's a physical change. The water goes from a liquid state to a solid state. But, the substance isn't changed: the compound is still H2O whether it's water or ice.
Another example would be cutting a cake. You make a physical change by cutting a slice out of the cake: you make it smaller. However, afterwards, the cake is still a cake. You didn't turn it into a pie or a muffin; it stayed the same thing, a cake, while just getting smaller.
Answer:
having half the swimmers first swim without fins and then with fins and having the other half swim first with fins and then without fins.
Explanation:
counterbalanced repeated measures is methodology of experimentation in which sample for experiment is divided into two parts equally. The first follows the condition of experiment in one series of step while other part follows the steps precisely opposite to that of first part. The objective of such methodology is to cover each condition of experimentation and nullify any error condition for every sample. It also makes sure that in series of steps, sequence does not affect the result.
Since in the above experiment Powel wants to counterbalancing first he needs to divide the sample of swimmer into two parts. Then both parts should follows opposite steps.
This can be best followed by
in first half sample
- test the speed of swimmer without fins
- then test the speed same set of swimmer without fin
- then see the discrepancy in the speed
second half sample
- test the speed of simmers with fins
- test their speed without fins.
- see the discrepancy in the speed
then compare the results of both set of sample. It will make sure that both half corroborate the same result, also sequence of with and without fins does not effect the result and produce biased result.
based on this option 3 is correct answer.