Problem: Classical music:

Vocal music in the Renaissance is noted for the flourishing of an increasingly elaborate polyphonic style. The principal liturgical forms which endured throughout the entire Renaissance period were masses and motets, with some other developments towards the end, especially as composers of sacred music began to adopt secular forms (such as the madrigal) for their own designs. Towards the end of the period, the early dramatic precursors of opera such as monody, the madrigal comedy, and the intermedio are seen.

Vocal music in the Renaissance is noted for an increasingly elaborate what?
---
A: polyphonic style

Problem: Videoconferencing:

Videoconferencing is a highly useful technology for real-time telemedicine and telenursing applications, such as diagnosis, consulting, transmission of medical images, etc... With videoconferencing, patients may contact nurses and physicians in emergency or routine situations; physicians and other paramedical professionals can discuss cases across large distances. Rural areas can use this technology for diagnostic purposes, thus saving lives and making more efficient use of health care money. For example, a rural medical center in Ohio, United States, used videoconferencing to successfully cut the number of transfers of sick infants to a hospital 70 miles (110 km) away. This had previously cost nearly $10,000 per transfer.

Where did a medical center use transmission of medical images to cut costs?
---
A: unanswerable

Problem: Federalism:

Federalism, and other forms of territorially autonomy, is generally seen as a useful way to structure political systems in order prevent violence among different groups with countries because it allows certain groups to legislate at the subnational level. Some scholars have suggested, however, that federalism can divide countries and result in state collapse because it creates proto-states. Still others have shown that federalism is only divisive when it lacks mechanisms tthat encourage political parties to compete across regional boundaries.

What doesn't federalism allow?
---
A: unanswerable

Problem: Printed circuit board:

Unpopulated boards are usually bare-board tested for "shorts" and "opens". A short is a connection between two points that should not be connected. An open is a missing connection between points that should be connected. For high-volume production a fixture or a rigid needle adapter is used to make contact with copper lands on the board. Building the adapter is a significant fixed cost and is only economical for high-volume or high-value production. For small or medium volume production flying probe testers are used where test probes are moved over the board by an XY drive to make contact with the copper lands. The CAM system instructs the electrical tester to apply a voltage to each contact point as required and to check that this voltage appears on the appropriate contact points and only on these.

A long is a connection between what?
---
A:
unanswerable