Question: In a WRIM, the rotor winding is made of many turns of insulated wire and is connected to slip rings on the motor shaft. An external resistor or other control devices can be connected in the rotor circuit. Resistors allow control of the motor speed, although significant power is dissipated in the external resistance. A converter can be fed from the rotor circuit and return the slip-frequency power that would otherwise be wasted back into the power system through an inverter or separate motor-generator.
Is there an answer to this question:  What can a resistor never control?

Answer: unanswerable


Question: A fervent follower of the absolutist cause, Elío had played an important role in the repression of the supporters of the Constitution of 1812. For this, he was arrested in 1820 and executed in 1822 by garroting. Conflict between absolutists and liberals continued, and in the period of conservative rule called the Ominous Decade (1823–1833), which followed the Trienio Liberal, there was ruthless repression by government forces and the Catholic Inquisition. The last victim of the Inquisition was Gaietà Ripoli, a teacher accused of being a deist and a Mason who was hanged in Valencia in 1824.
Is there an answer to this question: How was Elio executed?

Answer: by garroting


Question: Midtown Raleigh is a residential and commercial area just North of the I-440 Beltline and is part of North Raleigh. It is roughly framed by Glenwood/Creedmoor Road to the West, Wake Forest Road to the East, and Millbrook Road to the North. It includes shopping centers such as North Hills and Crabtree Valley Mall. It also includes North Hills Park and part of the Raleigh Greenway System. The term was coined by the Greater Raleigh Chamber of Commerce, developer John Kane and planning director Mitchell Silver. The News & Observer newspaper started using the term for marketing purposes only. The Midtown Raleigh Alliance was founded on July 25, 2011 as a way for community leaders to promote the area.
Is there an answer to this question: When was the Midtown Raleigh Alliance dissolved?

Answer: unanswerable


Question: Zhejiang, as the heartland of the Jiangnan (Yangtze River Delta), remained the wealthiest area during the Six Dynasties (220 or 222–589), Sui, and Tang. After being incorporated into the Sui dynasty, its economic richness was used for the Sui dynasty's ambitions to expand north and south, particularly into Korea and Vietnam. The plan led the Sui dynasty to restore and expand the network which became the Grand Canal of China. The Canal regularly transported grains and resources from Zhejiang, through its metropolitan center Hangzhou (and its hinterland along both the Zhe River and the shores of Hangzhou Bay), and from Suzhou, and thence to the North China Plain. The débâcle of the Korean war led to Sui's overthrow by the Tang, who then presided over a centuries-long golden age for the country. Zhejiang was an important economic center of the empire's Jiangnan East Circuit and was considered particularly prosperous. Throughout the Tang dynasty, The Grand Canal had remained effective, transporting grains and material resources to North China plain and metropolitan centers of the empire. As the Tang Dynasty disintegrated, Zhejiang constituted most of the territory of the regional kingdom of Wuyue.
Is there an answer to this question: Which dynasty restored and expanded the network that became the Grand Canal of China?

Answer:
the Sui dynasty