Victory for the ACT Student Text 15e

L ESSON 1 | D ATA R EPRESENTATION • 299 ‘” –Š‡ Š—ƒ ‡ƒ” –‘ Š‡ƒ” ƒ ʹͲǦŠ‡”–œ sound at a loudness of 70 phons, the SPL must be: F. 50 decibels. G. 75 decibels. H. 100 decibels. J. 110 decibels. 21. For the human ear to hear a minimum ƒ—†‹„Ž‡ ͵ͲǦŠ‡”–œ •‘—†ǡ –Š‡ —•– „‡ǣ A. 20 decibels. B. 40 decibels. C. 60 decibels. D. 80 decibels. 22. Š‡ ’‡”…‡‹˜‡† Ž‘—†‡•• ‘ˆ ƒ ͵ͲͲǦŠ‡”–œ sound with an SPL of 15 decibels is the •ƒ‡ ƒ• ƒ ͵ͲǦŠ‡”–œ •‘—† ™‹–Š ƒ ‘ˆǣ F. 50 decibels. G. 55 decibels. H. 62 decibels. J. 150 decibels. 20.

17. The range of maximum sensitivity for human hearing is approximately: Ǥ ͷͲ –‘ ͳͲͲ Š‡”–œǤ Ǥ ͳͲͲ –‘ ͷͲͲ Š‡”–œǤ Ǥ ͷͲͲ –‘ ͷǡͲͲͲ Š‡”–œǤ Ǥ ͶǡͲͲͲ –‘ ͸ǡͲͲͲ Š‡”–œǤ 18. Which of the following is a true statement regarding loudness and SPL? F. Loudness is measured in decibels; SPL is measured in phons. G. SPL is a measure of subjective quantity; phons may be measured with a sound level meter. H. Loudness is subjective, but related to SPL. J. For any given SPL, loudness remains constant for all frequencies. 19. ͵ͲͲǦŠ‡”–œ •‘—† ™‹–Š ƒ ‘ˆ 15 decibels has a loudness of: A. 10 phons. B. 20 phons. C. 30 phons. D. 40 phons.