A concept map for four types of intermolecular forces and a certain type of bond is shown. An ellipse is shown. Inside the ellipse is written Are ions present. An arrow from the right side of the ellipse has Yes written on it and points to another ellipse. This ellipse has Are polar molecules present written inside it. This ellipse has two arrows coming out of it. One arrow has Yes written on it and leads to a rectangular box that has D written inside it. The second arrow has No written on it and leads to a rectangular box that has E written inside it. An arrow from the left of the topmost ellipse has No written on it and leads to an ellipse that has Are molecules with permanent dipoles present Written on it. An arrow that has No written on it, points from this ellipse towards a rectangle that has A written inside it. An arrow that has Yes written on it, points from this ellipse towards another ellipse that has Is H atom bonded to F, O, or N atom Written on it. This ellipse also has two arrows coming from it. The arrow with Yes written on it leads to a rectangle that has C written on it and the arrow that has No written on it leads to a rectangle that has B written inside it. Compare the relative strength of the two forces A and B. Explain how you determined this comparison by identifying the forces.

describe matter a earth

gravity causes stares to cluster i think so

answer: you could do some invislibe ink.

explanation: i will tell you how to if u answer my question.

1. the question asks the most appropriate, which seems to rule out "all of the above." your choice appears to be the correct one.

2. the protocol described is good for identifying correlation, but not cause and effect. for cause/effect, you need to devise a protocol that will assign the treatment (or not) to groups that have essentially the same "demographics" with respect to all the other variables. your choice regarding control group seems appropriate. random assignment of treatment (choice d) may be appropriate also. (i think you can argue that b and d are just different descriptions of the same method.)

3. d will randomize the birds, but may not guarantee there are 10 in each group. e will do both, so seems the better choice.

comment on question 2

based on the problem statement, it seems clear that confident, attentive drivers are more likely to use daytime running lights. so, the protocol might need to be devised in such a way that the lights would be turned on or off without the driver's knowledge. (an attentive driver will figure it out.) assigning a confident, attentive driver to a group required to drive without running lights might mess with his/her confidence and attentiveness. you don't want your experiment to do that. (nor do you want the experiment to subject a driver to greater risk of accident as a consequence of driving without running lights.) experiments involving human safety are always problematic.