STAMPS ………A. CANNOT BE INVESTED B. ARE EASY TO STOREC. ARE NOT EAS...

34. Stamps ………a. cannot be invested b. are easy to storec. are not easy to store d. are unportable investmentsVI. Fill in each numbered blank with one suitable word or phrase. Astronauts (35) …. tied to something to prevent them floating around and bumping into equipment (36)……. they sleep. They may sleep in their seats or in upright lockers or (37) ……… tie themselves to thewall in a sleeping bag. Sometimes they forget to strap down and end up floating around inside the ship, much tothe (38) …….. of their fellow crewmembers.On some missions, all the crew sleep (39) ………… the same time but during others, they may (40)…………. round the clock in two shifts. As their ship traveling so fast, they see a sunrise every 90 minutes .