The speed of sound is approximately 740 m.p.h. A fire engine with its siren sounding is approaching you at 80 m.p.h. At what speed is the sound from the siren approaching you?
Buckminsterfullerine is a natural form of carbon consisting of 60 carbon atoms linked into an almost spherical C60 molecule. Which of the following does it consist of?
In mathematical equations the order of operations is multiplication before addition. What is the value of ? in {4[6 + (4 x 9 + 14)]} = ? Answer with a natural number.
What number should replace the question mark? Left column: 3829, 6952, 3521, 3235, 7669, 7338. Right column: 4873, 8176, 9632, 6912, 1825, ? Answer with a natural number.
Five suspects, one of whom is guilty, are being interrogated. Who is the culprit if exactly three of the following statements are correct? Alf: ‘Dave did it.’ Ben: ‘It wasn’t me.’ Charlie: ‘Ernie is innocent.’ Dave: ‘Alf is lying when he accuses me.’ Ernie: ‘Ben is telling the truth.’