29. In an eighth-grade science class, there are four lab groups. Group 4 designs an experiment to find out how light affects the germination rate of radish seeds. The students in Group 4 write out their procedure and
conduct their experiment. They discover inconsistencies in their data and decide to increase the number of
trials to obtain multiple data sets. Which of these most accurately describes how this should be done?
O Group 4 should repeat their procedure at least three times.
O Group 4 should repeat a revised procedure at least three times.
O Group 4 should communicate their procedure to another group for replication.
O Group 4 should communicate a revised procedure to another group for replication.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

the answer is a for sure mark brainliest i had got this right on usatestprep

4d^55s^1 ( third choice)