Problem: Richard Feynman:

He immersed himself in work on the project, and was present at the Trinity bomb test. Feynman claimed to be the only person to see the explosion without the very dark glasses or welder's lenses provided, reasoning that it was safe to look through a truck windshield, as it would screen out the harmful ultraviolet radiation. On witnessing the blast, Feynman ducked towards the floor of his truck because of the immense brightness of the explosion, where he saw a temporary "purple splotch" afterimage of the event.

What did Feynman see after the atomic test?
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A: "purple splotch" afterimage

Problem: Electric motor:

Perhaps the first electric motors were simple electrostatic devices created by the Scottish monk Andrew Gordon in the 1740s. The theoretical principle behind production of mechanical force by the interactions of an electric current and a magnetic field, Ampere's force law, was discovered later by Andre-Marie Ampere in 1820. The conversion of electrical energy into mechanical energy by electromagnetic means was demonstrated by the British scientist Michael Faraday in 1821. A free-hanging wire was dipped into a pool of mercury, on which a permanent magnet (PM) was placed. When a current was passed through the wire, the wire rotated around the magnet, showing that the current gave rise to a close circular magnetic field around the wire. This motor is often demonstrated in physics experiments, brine substituting for toxic mercury. Though Barlow's wheel was an early refinement to this Faraday demonstration, these and similar homopolar motors were to remain unsuited to practical application until late in the century.

In what year did Faraday convert electrical energy into mechanical energy?
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A: 1821

Problem: Madonna (entertainer):

In January 1989, Madonna signed an endorsement deal with soft-drink manufacturer, Pepsi. In one of her Pepsi commercials, she debuted her song "Like a Prayer". The corresponding music video featured many Catholic symbols such as stigmata and cross burning, and a dream of making love to a saint, leading the Vatican to condemn the video. Religious groups sought to ban the commercial and boycott Pepsi products. Pepsi revoked the commercial and canceled her sponsorship contract. The song was included on Madonna's fourth studio album, Like a Prayer, which was co-written and co-produced by Patrick Leonard and Stephen Bray. Madonna received positive feedback for the album, with Rolling Stone writing that it was "as close to art as pop music gets". Like a Prayer peaked at number one on the Billboard 200 and sold 15 million copies worldwide, with 4 million copies sold in the U.S. alone. Six singles were released from the album, including "Like a Prayer", which reached number one, and "Express Yourself" and "Cherish", both peaking at number two. By the end of the 1980s, Madonna was named as the "Artist of the Decade" by MTV, Billboard and Musician magazine.

When did Madonna sign an endorsement deal with Pepsi?
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A: January 1989

Problem: Punjab, Pakistan:

Exhibitions and annual horse shows in all districts and a national horse and cattle show at Lahore are held with the official patronage. The national horse and cattle show at Lahore is the biggest festival where sports, exhibitions, and livestock competitions are held. It not only encourages and patronises agricultural products and livestock through the exhibitions of agricultural products and cattle but is also a colourful documentary on the rich cultural heritage of the province with its strong rural roots.

What is Punjab's biggest festival?
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A:
The national horse and cattle show