Which of the following may cause the results of a naturalistic observation to be invalid? a. The presence of the researcher causing the observed behavior to change
b. Observer bias in the interpretation of the observed behavior
c. All of the above
d. Telling those who are being observed why they are being ​

The correct answer is C. All of the above.

Explanation

Naturalistic observation is a research method by observing a subject or group of individuals or animals directly in their place of residence. Another of its main characteristics is that the researcher must refrain from disturbing or intervening in the lives of those observed to avoid any interference that implies a different behavior than they would have if the observer were not there.

Therefore, it can be concluded that during a naturalistic observation the researcher should be prevented from having behavior that modifies the behavior of the observed group or individual; The observer must be prevented from making value judgments about the results obtained and from subjective or biased views, and the observer must avoid transmitting a message to the observed of how they should behave while they are observed because this can alter their actions. Therefore, the correct answer is C. All of the above.

we can solve this via the kinematic equation:

where the vertical velocity is zero and so:

since the height of the building is 29.3 meters then:

the ball was in motion for approximately 2.45 seconds