Article: To understand groups beyond the level of mere symbolic manipulations as above, more structural concepts have to be employed.c[›] There is a conceptual principle underlying all of the following notions: to take advantage of the structure offered by groups (which sets, being "structureless", do not have), constructions related to groups have to be compatible with the group operation. This compatibility manifests itself in the following notions in various ways. For example, groups can be related to each other via functions called group homomorphisms. By the mentioned principle, they are required to respect the group structures in a precise sense. The structure of groups can also be understood by breaking them into pieces called subgroups and quotient groups. The principle of "preserving structures"—a recurring topic in mathematics throughout—is an instance of working in a category, in this case the category of groups.

Question: What concept describes groups that can be related to each other via functions?
Ans: group homomorphisms


Article: In contrast, Botswana has recently been forced to ban trophy hunting following a precipitous wildlife decline. The numbers of antelope plummeted across Botswana, with a resultant decline in predator numbers, while elephant numbers remained stable and hippopotamus numbers rose. According to the government of Botswana, trophy hunting is at least partly to blame for this, but many other factors, such as poaching, drought and habitat loss are also to blame. Uganda recently did the same, arguing that "the share of benefits of sport hunting were lopsided and unlikely to deter poaching or improve [Uganda's] capacity to manage the wildlife reserves."

Question: What Botswana was resently forced to do?
Ans: ban trophy hunting


Article: Initially PCBs were designed manually by creating a photomask on a clear mylar sheet, usually at two or four times the true size. Starting from the schematic diagram the component pin pads were laid out on the mylar and then traces were routed to connect the pads. Rub-on dry transfers of common component footprints increased efficiency. Traces were made with self-adhesive tape. Pre-printed non-reproducing grids on the mylar assisted in layout. To fabricate the board, the finished photomask was photolithographically reproduced onto a photoresist coating on the blank copper-clad boards.

Question: What kind of metal coated the blank boards used to make PCBs?
Ans: copper


Article: Ogives are alternating wave crests and valleys that appear as dark and light bands of ice on glacier surfaces. They are linked to seasonal motion of glaciers; the width of one dark and one light band generally equals the annual movement of the glacier. Ogives are formed when ice from an icefall is severely broken up, increasing ablation surface area during summer. This creates a swale and space for snow accumulation in the winter, which in turn creates a ridge. Sometimes ogives consist only of undulations or color bands and are described as wave ogives or band ogives.

Question: How are ogives formed?
Ans:
when ice from an icefall is severely broken up, increasing ablation surface area during summer