Which of the following statements represents one of the differences between an experiment and an observational study? inclusion of random sample. introducing a change to the subgroup. ability to calculate the mean. ability to draw conclusions.

Introducing a change to the subgroup

Step-by-step explanation:

Given there are four statements.  We have to find the one which represents one of the differences between an experiment and an observational study.

The answer is option 2. Introducing a change to the subgroup

Experimental and observational studies are both types of studies between which a number of differences can be identified. When conducting research studies,  various types of research in order to arrive are adopted according to the need.  

An experimental study is a study where the researcher has control over most of the variables.

On the other hand, an observation study is a study where the researcher cannot control any variable but merely observes the subject without controlling any variables.

answer: i'm not going to give you the answer, but some hints to work it out.

step-by-step explanation: so, if there is a straight line that means that the line angle is 180°. so we subtract the 2 angle measures provided, (15 and 38) from 180. so the answer is 180 - (38 + 15). (you have to solve the equation)

the first one is x^2+2x+2

the second one is x^2+4

the last one is x^2-4x+8