Read the introduction to an argumentative essay.
(1) graffiti artists are gaining worldwide recognition for their
art work. (2) graffiti art deserves to be treated like "real" art
because, like other types of art, it has its own unique style,
contains artistic elements like color and composition, and
expresses the emotions and viewpoints of the artists.
how can the writer revise the introduction to be more effective?

By adding closing sentence

Explanation:

The introduction will be more effective if the writer would add a closing sentence. The main idea of closing sentences is to establish and restates the most important thing about the argumentative essay, to show what are the key and the main idea of that essay.

This introduction needs strength and stable information because these pieces of information are incomplete and they are left hanging. Because it is the argumentative essay it would be good to be clear about what the author is arguing and what is he trying to describe.  

that is literally a whole assignment and i'm not sure anyone in their right mind or even wrong mind is going to do an entire assignment for someone just for 100 points on a website. sorry to tell you like