Keera decided to investigate how the growth of plants is affected by the time of day it is watered. she placed an equal amount of potting soil in three identical pots and planted three bean plants in each pot. the pots were placed on the same table so that they received the same amount of light. one pot was watered at sunrise, one at noon, and the last pot at sunset. after ten days, the height of each individual plant was measured and recorded. what is the independent variable in this investigation?

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.

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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.