TASK DEFINITION: This task is about reading the given passage and construct a question about the information present in the passage. Construct a question in such a way that (i) it is unambiguous, (ii) it is answerable from the passage, (iii) its answer is unique (iv) its answer is a continuous text span from the paragraph. Avoid creating questions that (i) can be answered correctly without actually understanding the paragraph and (ii) uses same words or phrases given in the passage.
PROBLEM: Israel is widely believed to possess nuclear weapons as well as chemical and biological weapons of mass destruction. Israel has not signed the Treaty on the Non-Proliferation of Nuclear Weapons and maintains a policy of deliberate ambiguity toward its nuclear capabilities. The Israeli Navy's Dolphin submarines are believed to be armed with nuclear Popeye Turbo missiles, offering nuclear second strike capability. Since the Gulf War in 1991, when Israel was attacked by Iraqi Scud missiles, all homes in Israel are required to have a reinforced security room, Merkhav Mugan, impermeable to chemical and biological substances.

SOLUTION: Israel is widely believed to possess what?

PROBLEM: Around 2.5 million years ago (ending 11,600 years ago) was the geological period of the Ice Ages. Since approximately 600,000 years ago, six major Ice Ages have occurred, in which sea level dropped 120 m (390 ft) and much of the continental margins became exposed. In the Early Pleistocene, the Rhine followed a course to the northwest, through the present North Sea. During the so-called Anglian glaciation (~450,000 yr BP, marine oxygen isotope stage 12), the northern part of the present North Sea was blocked by the ice and a large lake developed, that overflowed through the English Channel. This caused the Rhine's course to be diverted through the English Channel. Since then, during glacial times, the river mouth was located offshore of Brest, France and rivers, like the Thames and the Seine, became tributaries to the Rhine. During interglacials, when sea level rose to approximately the present level, the Rhine built deltas, in what is now the Netherlands.

SOLUTION: What period was 2.5 million years ago?

PROBLEM: In 1983, the International Telecommunication Union's radio telecommunications sector (ITU-R) set up a working party (IWP11/6) with the aim of setting a single international HDTV standard. One of the thornier issues concerned a suitable frame/field refresh rate, the world already having split into two camps, 25/50 Hz and 30/60 Hz, largely due to the differences in mains frequency. The IWP11/6 working party considered many views and throughout the 1980s served to encourage development in a number of video digital processing areas, not least conversion between the two main frame/field rates using motion vectors, which led to further developments in other areas. While a comprehensive HDTV standard was not in the end established, agreement on the aspect ratio was achieved.

SOLUTION:
When did ITU-R start trying to work towards setting a single international HDTV standard?