Problem: Data compression can be viewed as a special case of data differencing: Data differencing consists of producing a difference given a source and a target, with patching producing a target given a source and a difference, while data compression consists of producing a compressed file given a target, and decompression consists of producing a target given only a compressed file. Thus, one can consider data compression as data differencing with empty source data, the compressed file corresponding to a "difference from nothing." This is the same as considering absolute entropy (corresponding to data compression) as a special case of relative entropy (corresponding to data differencing) with no initial data.
What is made up of producing a difference given a source and a target?
The answer is the following: Data differencing

Problem: Montana is home to a diverse array of fauna that includes 14 amphibian, 90 fish, 117 mammal, 20 reptile and 427 bird species. Additionally, there are over 10,000 invertebrate species, including 180 mollusks and 30 crustaceans. Montana has the largest grizzly bear population in the lower 48 states. Montana hosts five federally endangered speciesblack-footed ferret, whooping crane, least tern, pallid sturgeon and white sturgeon and seven threatened species including the grizzly bear, Canadian lynx and bull trout. The Montana Department of Fish, Wildlife and Parks manages fishing and hunting seasons for at least 17 species of game fish including seven species of trout, walleye and smallmouth bass and at least 29 species of game birds and animals including ring-neck pheasant, grey partridge, elk, pronghorn antelope, mule deer, whitetail deer, gray wolf and bighorn sheep.
What type of bear does Montana have the highest population of?
The answer is the following: grizzly bear

Problem: While the number of cardinals was small from the times of the Roman Empire to the Renaissance, and frequently smaller than the number of recognized churches entitled to a cardinal priest, in the 16th century the College expanded markedly. In 1587, Pope Sixtus V sought to arrest this growth by fixing the maximum size of the College at 70, including 50 cardinal priests, about twice the historical number. This limit was respected until 1958, and the list of titular churches modified only on rare occasions, generally when a building fell into disrepair. When Pope John XXIII abolished the limit, he began to add new churches to the list, which Popes Paul VI and John Paul II continued to do. Today there are close to 150 titular churches, out of over 300 churches in Rome.
Who removed the cap on cardinals in the College of the Cardinals?
The answer is the following: Pope John XXIII

Problem: Victoria visited mainland Europe regularly for holidays. In 1889, during a stay in Biarritz, she became the first reigning monarch from Britain to set foot in Spain when she crossed the border for a brief visit. By April 1900, the Boer War was so unpopular in mainland Europe that her annual trip to France seemed inadvisable. Instead, the Queen went to Ireland for the first time since 1861, in part to acknowledge the contribution of Irish regiments to the South African war. In July, her second son Alfred ("Affie") died; "Oh, God! My poor darling Affie gone too", she wrote in her journal. "It is a horrible year, nothing but sadness & horrors of one kind & another."
Which of Queen Victoria's children died in July of that year?
The answer is the following:
her second son Alfred