Please quickly Proofread the paragraph.
Roland was walking through the desert. The sun is setting, and he felt a chill. He carried his telescope and star map with him. He finds the
perfect spot, level and away from the road, and set up his tripod. He sat on the ground, crossed his legs, and waits for night to fall.

Which kind of error needs to be fixed?

O 1. run-on sentence

2. spelling

3verb tense inconsistencies

4. sentence fragment

The kind of error that needs to be fixed is:

3 verb tense inconsistencies

Explanation:

There are no run-on sentences, misspellings, or sentence fragments in the paragraph we are analyzing here. There are, however, verb tense inconsistencies. The narration begins in the past tense but, all of a sudden, a verb in the present appears. The pattern repeats throughout the passage, with verbs in the past and in the present being alternated. A way to correct such inconsistencies would be by simply using only past forms for all the verbs:

Roland was walking through the desert. The sun was setting, and he felt a chill. He carried his telescope and star map with him. He found the  perfect spot, level and away from the road, and set up his tripod. He sat on the ground, crossed his legs, and waited for night to fall.

the best sentence that shows the best placement for the modifier "on the ice" is the one which contains it in the end of the sentence or in its beggining followed by a comma, that indicates it works as adverbial, dislocated in the sentence.

the girl promptly slid on her rollers on the ice.

on the ice, the girl promptly slid on her rollers.

incoherently means without logical or meaningful connection; disjointed rambling an incoherent sentence. characterized by such thought or language.