Atoms form ions that have the same number of blank as noble gases

Iknow the answer to 13 is b and 14 is d. i just need to know why the correct answers are correct

The diagram shows the positions of the sun, moon and earth during spring tides, when the high tides are at their highest and low tides at their lowest. what is it about these positions that causes these high and low tides?

Use the de broglie's wave equation to find the wavelength of an electron moving at 4.5 × 106 m/s. show your work. note: h= plank's constant (6.62607 x 10-34 j s)