9. Under what conditions would you expect to see a full moon? (Hint: think about where the moon is in relation to the sun and to Earth)

Under what conditions would you expect to see a new moon?

10. How do the Moon and the Sun affect Earth's oceans?

11. Why do you think it is important for people to know when the tides will be
high and/or low?

i just got this problem. it's 90.3

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.  

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)