Ascientist is using sonar to map the ocean floor while traveling on the ocean surface in a ship. she observes that the first sound pulse returns from the ocean floor much more quickly than the second sound pulse. what can she conclude based on this information?

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.