An electrically neutral atom of oxygen has eight electrons. what other facts do you know for sure about this atom? there are eight neutrons in the nucleus. there are eight protons. there is a charge of +8 on an atom of beryllium. there is a charge of 8 on an atom of beryllium.

There are eight protons.

Explanation:

Mass number is the sum of total number of protons and neutrons present in the nucleus of an atom.

On the other hand, atomic number is only the total number of protons present in an atom.

Also, when an atom is electrically neutral in nature then its number of protons equal to the number of electrons present in it.

An electrically neutral atom of oxygen has 8 electrons and 8 protons. It can have any number of neutrons depending on the isotope of oxygen.

Thus, we can conclude that an electrically neutral atom of oxygen that has eight electrons will also have 8 protons.

answer; i believe that the correct answer is (a) potassium(k)

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.