Question

which is a run - on sentence? we cant see atoms with the naked eye, but they do exist. well need a detour around the flooded road, heres an alternate route. made both of the pie crusts with lard instead of butter.

Explanation:

A run - on sentence combines two or more independent clauses without proper punctuation or conjunctions. The first sentence has a coordinating conjunction "but" to join two clauses. The third sentence is a sentence fragment as it lacks a subject. The second sentence "We'll need a detour around the flooded road, here's an alternate route." combines two independent clauses ("We'll need a detour around the flooded road" and "here's an alternate route") with just a comma, which is a run - on.

Answer:

We'll need a detour around the flooded road, here's an alternate route.