Which substance is organic?

sodium cyanide, nacn
the mineral magnesite, mgco3
carbon monoxide gas, co
the sugar sucrose, c12h22o11

meteorologists would compare a new weather map with one 24 h old to see how fast a front is moving.

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.