Theo M. answered 13d
Language nerd, math nerd, music nerd, coding nerd
Esta / este, estas / estos = this, these (next to the speaker)
Esa / ese, esas / esos = that, those (near the speaker)
Aquella / aquel, aquellas / aquellos = that, those (far from the speaker)
al lado = next to
cerca = near
lejos = far