Question

insert one comma to separate the coordinate adjectives. , volcanic ash, which has an abrasive sandy texture, can include various identifiable particles: crystals, minerals, bits of pumice, shards of volcanic glass, and miscellaneous rock fragments.

Explanation:

Step1: Identify coordinate adjectives

In the phrase "abrasive sandy texture", "abrasive" and "sandy" are coordinate adjectives (they both describe "texture" and their order can be reversed or separated by "and" logically).

Step2: Insert comma

Place a comma between "abrasive" and "sandy" to separate the coordinate adjectives.

Answer:

Volcanic ash, which has an abrasive, sandy texture, can include various identifiable particles: crystals, minerals, bits of pumice, shards of volcanic glass, and miscellaneous rock fragments.