Sodium-24 has a half-life of 15 hours. What mass in grams of Na-24 will remain in an 18.0 g sample after 90 hours?

The diagrams show objects’ gravitational pull toward each other. which statement describes the relationship between diagram x and y? gravity attracts only larger objects toward one another. gravity attracts larger objects only if they are close to one another. if the masses of the objects increase, then the force between them also increases. if distance between the objects increases, then the amount of force also increases.