_________, a cool little game where kids build molecules out of atoms 

________construction includng lines and circle and their properties had been developed by humans ever since early ages.

________means to enlarge somthething.

__________ is a periodic table viewer that provides detailed information on the chemical elements.

_______ is a desktop environment for Linux based operation system. 

__________ is a 3D astronomy program 

Software used to represent day and night at a given time

____________tool used to control the lengths of lines,the angle sizes etc.