Problem: Canadian Armed Forces:

Consistent with the missions and priorities outlined above, the Canadian Armed Forces also contribute to the conduct of Canadian defence diplomacy through a range of activities, including the deployment of Canadian Defence Attaches, participation in bilateral and multilateral military forums (e.g. the System of Cooperation Among the American Air Forces), ship and aircraft visits, military training and cooperation, and other such outreach and relationship-building efforts.

How does the Armed Canadian Forces contribute to the conduct of Canadian defence diplomacy?
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A: unanswerable

Problem: Law of the United States:

Notably, a statute does not disappear automatically merely because it has been found unconstitutional; it must be deleted by a subsequent statute. Many federal and state statutes have remained on the books for decades after they were ruled to be unconstitutional. However, under the principle of stare decisis, no sensible lower court will enforce an unconstitutional statute, and any court that does so will be reversed by the Supreme Court. Conversely, any court that refuses to enforce a constitutional statute (where such constitutionality has been expressly established in prior cases) will risk reversal by the Supreme Court.

What can delete a statute and make it unconstitutional?
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A: a subsequent statute

Problem: Light-emitting diode:

LEDs have been developed by Seoul Semiconductor that can operate on AC power without the need for a DC converter. For each half-cycle, part of the LED emits light and part is dark, and this is reversed during the next half-cycle. The efficacy of this type of HP-LED is typically 40 lm/W. A large number of LED elements in series may be able to operate directly from line voltage. In 2009, Seoul Semiconductor released a high DC voltage LED, named as 'Acrich MJT', capable of being driven from AC power with a simple controlling circuit. The low-power dissipation of these LEDs affords them more flexibility than the original AC LED design.

What is so good about ac powered HP-LEDs?
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A: more flexibility

Problem: Wayback Machine:

Since 1996, they have been archiving cached pages of web sites onto their large cluster of Linux nodes. They revisit sites every few weeks or months and archive a new version if the content has changed. Sites can also be captured on the fly by visitors who are offered a link to do so. The intent is to capture and archive content that otherwise would be lost whenever a site is changed or closed down. Their grand vision is to archive the entire Internet.

When does Wayback Machine save a copy of a website?
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A:
if the content has changed