86. Artificial flowers are used for scientific as well as for decorative purposes. They are made from a variety of materials, such as way and glass, so skillfully that they can scarcely be distinguished from natural flowers.

87. Three years of research at an abandoned coal mine in Argonne, Illinois, have resulted in findings that scientists believe can help reclaim thousands of mine disposal sites that scar the coal-rich regions of the United States.

88. When the persuading and the planning for the western railroads had finally been completed, the really challenging task remained: the dangerous, sweaty, backbreaking, brawling business of actually building the lines.

89. Because of the space crunch, the Art Museum has become increasingly cautious in considering acquisitions and donations of art, in some cases passing up opportunities to strengthen is collections.

90. The United States Constitution requires that President be a natural-born citizen, thirty-five years of age or older, who has lived in the United States for a minimum of fourteen years.

91. Arid regions in the southwestern United States have become increasingly inviting playgrounds for the growing number of recreation seekers who own vehicles such as motorcycles or powered trail bikes and indulge in hill-climbing contests or in caving new trails in the desert.

92. Stone does decay, and so tools of long ago have remained when even the bones of the man who made them have disappeared without trace.

93. Insects would make it impossible for us to live in the world; they would devour all our crops and kill our flocks and herds, if it were not for the protection we get from insect-eating animals.

94. It is true that during their explorations they often faced difficulties and dangers of the most perilous nature, equipped in a manner which would make a modern climber shudder at the thought, but they did not go out of their way to court such excitement.

95. There is only onedifference between an old man and a young one: the young man has a glorious future before him and old one has a splendid future behind him: and maybe that is where the rub is.

96. I find young people exciting. They have an air of freedom, and they have not a dreary commitment to mean ambitions or love comfort. They are not anxious social climbers, and they have no devotion to material things.

97. I am always amazed when I hear people saying that sport creates goodwill between the nations, and that if only the common peoples of the world could meet one another at football or cricket, they would have no inclination to meet on the battlefield.

98. It is impossible to say simply for the fun and exercise: as soon as the question of prestige arises, as soon as you feel that you and some larger unit will be disgraced if you lose, the most savage combative instincts are around.

99. It has been found that certain bats emit squeaks and by receiving the echoes, they can locate and steer clear of obstacles------or locate flying insects on which they feed. This echo-location in bats is often compared with radar, the principle of which is similar.