Select two
the two methods used for determining mass are:

1 measuring directly on a scale
2 measuring directly on a balance
3 calculated by measurements of w and g

Question:

The two methods used for determining mass are: measuring directly on a scale measuring directly on a balance measuring directly by displacement of water calculated by measurements of w and g

The two methods used for determining mass are measuring directly on a balance and measuring directly by displacement of water.

Explanation:

Mass is the actual content of the body, and when it is under some gravity, it becomes weight. But, mass cannot be calculated using any scale. It can be determined by using balance, as well as by a weight machine.

But, what is true here is that the mass of a body cannot be measured directly. It should be directly measured using water displacement. Because the displaced amount of water is equal to the volume of the objects.

the answer would be c

thermal energy is the answer