Problem: USB:

The USB Battery Charging Specification Revision 1.2 (released in 2010) makes clear that there are safety limits to the rated current at 5 A coming from USB 2.0. On the other hand, several changes are made and limits are increasing including allowing 1.5 A on charging downstream ports for unconfigured devices, allowing high speed communication while having a current up to 1.5 A, and allowing a maximum current of 5 A. Also, revision 1.2 removes support for USB ports type detection via resistive detection mechanisms.

What does the USB Battery Charging Specification Revision 1.2 make clear of?
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A: there are safety limits to the rated current at 5 A coming from USB 2.0


Problem: Predation:

The elimination of wolves from Yellowstone National Park had profound impacts on the trophic pyramid. Without predation, herbivores began to over-graze many woody browse species, affecting the area's plant populations. In addition, wolves often kept animals from grazing in riparian areas, which protected beavers from having their food sources encroached upon. The removal of wolves had a direct effect on beaver populations, as their habitat became territory for grazing. Furthermore, predation keeps hydrological features such as creeks and streams in normal working order. Increased browsing on willows and conifers along Blacktail Creek due to a lack of predation caused channel incision because they helped slow the water down and hold the soil in place.

Loose soil from lack of trees along the river bed resulted in?
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A: channel incision


Problem: Dwight D. Eisenhower:

Eisenhower did provide France with bombers and non-combat personnel. After a few months with no success by the French, he added other aircraft to drop napalm for clearing purposes. Further requests for assistance from the French were agreed to but only on conditions Eisenhower knew were impossible to meet – allied participation and congressional approval. When the French fortress of Dien Bien Phu fell to the Vietnamese Communists in May 1954, Eisenhower refused to intervene despite urgings from the Chairman of the Joint Chiefs, the Vice President and the head of NCS.

What arguably impossible conditions did Eisenhower set for further intervention on behalf of the French?
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A: allied participation and congressional approval


Problem: USB:

The connector construction always ensures that the external sheath on the plug makes contact with its counterpart in the receptacle before any of the four connectors within make electrical contact. The external metallic sheath is typically connected to system ground, thus dissipating damaging static charges. This enclosure design also provides a degree of protection from electromagnetic interference to the USB signal while it travels through the mated connector pair (the only location when the otherwise twisted data pair travels in parallel). In addition, because of the required sizes of the power and common connections, they are made after the system ground but before the data connections. This type of staged make-break timing allows for electrically safe hot-swapping.

Where is the external metallic sheet connected?
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A:
typically connected to system ground