Read this excerpt from “president ronald reagan's address to the nation” following the explosion of the challenger space shuttle. nineteen years ago, almost to the day, we lost three astronauts in a terrible accident on the ground. but we've never lost an astronaut in flight; we've never had a tragedy like this. and perhaps we've forgotten the courage it took for the crew of the shuttle. how is repetition used in this excerpt? a)the contraction “we’ve” is used three times to express sadness. b)the contraction “we’ve” is used three times to express courage. c)the contraction “we’ve” is used three times to express unity. d)the contraction “we’ve” is used three times to express terror.