I know that the density of 0.8505 is close to the actual value, I just can’t figure out if the tendline aligns or if the r^2 value is good?

Sally is making a model of a magnesium atom with an atomic mass number of 24 for her chemistry class. she has foam balls for the protons, neutrons, and electrons. she has added 6 neutrons to her model so far. how many more neutrons does she need to add to complete her neutral atom of magnesium?

What must occur for air masses to form fronts

When did stem cell research become known ? who discovered stem cell? what experiments or studies have been conducted so far?