On an international level the German DIN 4512 system has been effectively superseded in the 1980s by ISO 6:1974, ISO 2240:1982, and ISO 5800:1979 where the same sensitivity is written in linear and logarithmic form as "ISO 100/21" (now again with degree symbol). These ISO standards were subsequently adopted by DIN as well. Finally, the latest DIN 4512 revisions were replaced by corresponding ISO standards, DIN 4512-1:1993-05 by DIN ISO 6:1996-02 in September 2000, DIN 4512-4:1985-08 by DIN ISO 2240:1998-06 and DIN 4512-5:1990-11 by DIN ISO 5800:1998-06 both in July 2002.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What did the German DIN 4512 supersede?
Ah, so.. unanswerable

DEC operating systems (OS/8, RT-11, RSX-11, RSTS, TOPS-10, etc.) used both characters to mark the end of a line so that the console device (originally Teletype machines) would work. By the time so-called "glass TTYs" (later called CRTs or terminals) came along, the convention was so well established that backward compatibility necessitated continuing the convention. When Gary Kildall cloned RT-11 to create CP/M he followed established DEC convention. Until the introduction of PC DOS in 1981, IBM had no hand in this because their 1970s operating systems used EBCDIC instead of ASCII and they were oriented toward punch-card input and line printer output on which the concept of carriage return was meaningless. IBM's PC DOS (also marketed as MS-DOS by Microsoft) inherited the convention by virtue of being a clone of CP/M, and Windows inherited it from MS-DOS.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): What programming did IBM use in the 1970s?
Ah, so.. EBCDIC

Travel and tourism continue to be extremely important for Portugal, with visitor numbers forecast to increase significantly in the future.[citation needed] However, the increasing competition from Eastern European destinations continues to develop, with the presence of similar attractions that are often cheaper in countries such as Croatia. Consequently, it has been necessary for the country to focus upon its niche attractions, such as health, nature and rural tourism, to stay ahead of its competitors.
If it is possible to answer this question, answer it for me (else, reply "unanswerable"): With what area does Portugal compete with for tourists?
Ah, so..
Eastern European destinations