Which statement about the physical change of liquid water boiling into steam is true?
a. the heat added represents an energy change
b. the action cannot be reversed
c. the steam cannot conserve mass
d. the weight lost represents a mass change.

Answer;

The heat added represents an energy change.

Explanation;

-Physical changes are changes affecting the form of a chemical substance, but not its chemical composition.

-Physical changes are used to separate mixtures into their component compounds, but can not usually be used to separate compounds into chemical elements or simpler compounds.

Examples of Physical changes:

the simple machine has three main features. they are:

fulcrum is the center point or pivot point of the machine. effort is input force/ applied force. load is external force/ output.

the keisha 's machine labels are

x : load

y: fulcrum

z: lever

a) electrical > light, sound, and thermal< < < <

) the mechanical energy of the firefighter moving.< < < < a) electrical > light, sound, and thermal< < < <

c) both a and b.