Read the following passage carefully and then choose the right word to complete the sentence that follows. Rockets are very expensive as it can be used only once. Scientists have therefore developed a reusable space-craft called a space shuttle which takes off like a rocket but does bot get destroyed as it comes back to earth. It can also be used to launch satellites into space,  retrieve them from space if any repairing is needed and allow about 7-8 scientists to carry out experiments in space.The space shuttle does not get --