When frozen carbon dioxide (CO2) is heated, it changes directly into a gas. Which statement BEST indicates that a physical change has taken place?
a. Heat caused an increase in gas production.
b. Heat caused a new substance to form.
c. Heat caused a decrease in energy.
d. Heat caused a change in state.

answer: c

explanation:

what are the awnser choices? i mean, without choices, it is an incompleat

the correct answer is option d.

an appositive is a noun, noun phrase or noun clause which follows another noun or noun phrase in order to describe it or name it another way. they are usually used between commas, brackets or dashes.

the example sentence with the correct use of commas is the following:

her uncle, the man over there in the red shirt, owns the hardware store in town.

density and pressure