1. Which time word can we not use with the present perfect? * a) since
b) for
c) ago
d) before

The word "space" is translated from the greek means "peace" , "universe" . from the greek word "space" has passed into modern science , as a synonym of the universe. space includes an interplanetary , interstellar , intergalactic space with all the objects within it . space - it's a huge space , and it is becoming more and more. our entire solar system is only a small part of the cosmos. everything that happens in space affects the objects in it, and that is for each of us .the study of what happens in space, helps people in the world to take the necessary measures to preserve life. with the help of spacecraft launched from earth , it is possible not only to observe the processes that occur on our planet , but also to take timely and appropriate action. for example , you can be forewarned about some natural phenomena : the strong hurricanes , floods , magnetic storms and other .to study and use of outer space and the human race is constantly reinventing launches into space more and more spacecraft. today, there are a huge amount of space satellites , by which the world is television , telephone and radio communications.launched from earth spacecraft sent to different planets of the solar system : mars, saturn , venus, pluto and others. and the moon is visited not only spaceships, but the people in them were american astronauts . on the moon, discovered large reserves of helium . when it becomes possible shipping it back to earth , the earth's fuel resources will increase by several hundred years.by studying the processes occurring in space, scientists make predictions of the earth's climate and environmental develop recommendations for the conservation of nature.we know that over billions of years, life on earth will cease , so now the question becomes relevant search objects in space, which in the future would be suitable for life. we wonder if there is life on other solar systems and other galaxies , is there intelligent beings in the universe , is it possible to establish contact with them . to all this, today directed the efforts of mankind. a little more than fifty years , as the man launched into space the first machines, and how many new, interesting and useful things we have learned. and ahead of humanity still many, many millions of years , which will allow us to penetrate deeper into the mysteries of the universe and save lives in the future , which originated on earth.the study of space and its use for the benefit of humanity becomes more intense , and presents us with the first lessons . in space is becoming more and more man-made flying objects , the work and the mission of which need to be vigilant in order to avoid unpleasant consequences. in february 2009, encountered in space satellites the united states and russia . their collision formed large debris that are dangerous to other aircraft , and above all, for the international space station , which is operated by researchers from russia , the u.s. and other countries. we must make greater use of methods developed in the world and the means of clearing space debris .the universe or cosmos - is the whole world around us. all the heavenly bodies go through a complicated path of development. but no matter how they have changed , that of which they are composed (matter ) , indestructible , so the universe is not only infinite, but eternal. that is , for all these reasons i am very interested in space . all that is said here , i learned from a book by the english writer clive gifford "space : records and facts" encyclopedia "stars and planets " and the magazine "young scholar ".