Which sentence from the passage best supports the idea that before Salk's team, medical researchers had been unable to combat polio effectively? A. Building on the research of previous scientists and doctors, Salk developed a polio vaccine by growing large numbers of the virus in test tubes.

B. Analyzing their test results, Salk and his team were thrilled to see that their vaccine caused the immune system to produce polio antibodies without making a person ill.

C. In 1952, the United States dealt with 57,000 cases of polio—the most cases ever in a single year.

D. The next year, scientists announced that the vaccination trial had been a success: the vaccine prevented polio infections in 80% to 90% of people.

Read the excerpt from martin luther king jr.’s "i have a dream” speech. and so let freedom ring from the prodigious hilltops of new hampshire. let freedom ring from the mighty mountains of new york. let freedom ring from the heightening alleghenies of pennsylvania. let freedom ring from the snow-capped rockies of colorado. let freedom ring from the curvaceous slopes of california. but not only that: let freedom ring from stone mountain of georgia. let freedom ring from lookout mountain of tennessee. let freedom ring from every hill and molehill of mississippi. from every mountainside, let freedom ring. the most likely reason king uses allusions in this part of his speech is to share his knowledge of american geography. compare northern and southern destinations. remind listeners about small-town accountability. encourage listeners to envision freedom everywhere.

How do pip's feelings of guilt in chapter 6 fluctuate? a. he feels both guilty and exhilarated by the opportunity to interact with a convict. b. he doesn't feel any true guilt, but rather fear that he will be caught and self-loathing that he stole. c. he feels guilty, but only until the convict is found. d. he feels guilty for lying to joe, but not for stealing from mrs. joe, because he doesn't love her.

2pointsread this passage: "don't worry about me," i said. "i'm not tired at all." oh no, i'm feeling dizzy. this is what they call passing out. don'tdo that. don't pass out. stay upright – stay awake. how does the difference between the character's spoken words and internalthoughts affect the story? oa. it establishes the setting. ob. it introduces a new character. c. it creates dramatic tension. d. it ties up loose ends.