In the image which element is the most massive ?

that one

Explanation:

actually if u look very closely u can notice that the taco has some dog tird cover up with the rat tail and topped with some soymilk

fluorine

Explanation: it has the largest mass number which is almost rounded to 19.

a lot of it means it can be "burned" for energy and sold at one price. if it is scarce, the price will go up

molecules are free to separate from each other and will take on the shape of the container. molecules move completely at random and high speeds. they vibrate in a fixed position and do not move around much. molecules expand to the edge of their container.