How many mL of 0.50 M KCl solution must be diluted to prepare 210 mL of 0.10 M KCl?

i think it is d. e because the next one is igneous.

yes they ca   is ur ansswerrr

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.

there is none because earth is stationary and flat.