1 Cropping an image means to select a rectangular region to use. 2  To crop an image: 3  Right click on the image file in the File Explorer, select Open With, Paint. 4  Right click on the Select item in the toolbar.  Depress the left mouse button at the upper left corner of the rectangular region you wish to select.
TNT is made by adding 3 NO 2 groups (from nitric acid) to toluene. At low temperatures, the mononitrotoluenes are made, and as the reaction temperature is increased the dinitro compounds are formed, until eventually TNT is formed. TNT is explosive for two reasons. First, it contains the elements carbon, oxygen and nitrogen, which means that when the material burns it produces highly stable substances (CO, CO 2 and N 2) with strong bonds, so releasing a great deal of energy.
Learn about the basic ingredients of concrete, mix designs, and types of cement. Contrary to popular belief, concrete and cement are not the same thing; cement is actually just a component of concrete. Concrete is made up of three basic components: water, aggregate (rock, sand, or gravel) and Portland cement.Cement, usually in powder form, acts as a binding agent when mixed with water and aggregates.earn about the basic ingredients of concrete, mix designs, and types of cement. Contrary to popular belief, concrete and cement are not the same thing; cement is actually just a component of concrete. Concrete is made up of three basic components: water, aggregate (rock, sand, or gravel) and Portland cement.