The Hephthalites (or Ephthalites), also known as the White Huns, were a nomadic confederation in Central Asia during the late antiquity period. The White Huns established themselves in modern-day Afghanistan by the first half of the 5th century. Led by the Hun military leader Toramana, they overran the northern region of Pakistan and North India. Toramana's son Mihirakula, a Saivite Hindu, moved up to near Pataliputra to the east and Gwalior to the central India. Hiuen Tsiang narrates Mihirakula's merciless persecution of Buddhists and destruction of monasteries, though the description is disputed as far as the authenticity is concerned. The Huns were defeated by the Indian kings Yasodharman of Malwa and Narasimhagupta in the 6th century. Some of them were driven out of India and others were assimilated in the Indian society.
Where did the White Huns roam?
Central Asia

In September 2003, a new type of blue LED was demonstrated by Cree that consumes 24 mW at 20 milliamperes (mA). This produced a commercially packaged white light giving 65 lm/W at 20 mA, becoming the brightest white LED commercially available at the time, and more than four times as efficient as standard incandescents. In 2006, they demonstrated a prototype with a record white LED luminous efficacy of 131 lm/W at 20 mA. Nichia Corporation has developed a white LED with luminous efficacy of 150 lm/W at a forward current of 20 mA. Cree's XLamp XM-L LEDs, commercially available in 2011, produce 100 lm/W at their full power of 10 W, and up to 160 lm/W at around 2 W input power. In 2012, Cree announced a white LED giving 254 lm/W, and 303 lm/W in March 2014. Practical general lighting needs high-power LEDs, of one watt or more. Typical operating currents for such devices begin at 350 mA.
What is the typical operating current for high-power LEDs?
350 mA

Iran has the second largest proved gas reserves in the world after Russia, with 33.6 trillion cubic metres, and third largest natural gas production in the world after Indonesia, and Russia. It also ranks fourth in oil reserves with an estimated 153,600,000,000 barrels. It is OPEC's 2nd largest oil exporter and is an energy superpower. In 2005, Iran spent US$4 billion on fuel imports, because of contraband and inefficient domestic use. Oil industry output averaged 4 million barrels per day (640,000 m3/d) in 2005, compared with the peak of six million barrels per day reached in 1974. In the early years of the 2000s (decade), industry infrastructure was increasingly inefficient because of technological lags. Few exploratory wells were drilled in 2005.
What is Iran ranked in the world in proved gas reserves?
second largest