Answer:
Malcolm X predicts that people in America would be "astounded" by his letter on page 346 because most of them had already developed a "hate" image about him.
Step-by-step explanation:
All most Americans knew about Malcolm X was his rejection of the white race and aggressive fight for equality. After his visit to Mecca, he came back to America with a different view on race, a positive one, that people hadn't expected because they had already formed an image of him that was different from this one.