Input: MP3
Compression efficiency of encoders is typically defined by the bit rate, because compression ratio depends on the bit depth and sampling rate of the input signal. Nevertheless, compression ratios are often published. They may use the Compact Disc (CD) parameters as references (44.1 kHz, 2 channels at 16 bits per channel or 216 bit), or sometimes the Digital Audio Tape (DAT) SP parameters (48 kHz, 216 bit). Compression ratios with this latter reference are higher, which demonstrates the problem with use of the term compression ratio for lossy encoders.

What does CD stand for?
Output: Compact Disc

Input: Group (mathematics)
In the groups Z/nZ introduced above, the element 1 is primitive, so these groups are cyclic. Indeed, each element is expressible as a sum all of whose terms are 1. Any cyclic group with n elements is isomorphic to this group. A second example for cyclic groups is the group of n-th complex roots of unity, given by complex numbers z satisfying zn = 1. These numbers can be visualized as the vertices on a regular n-gon, as shown in blue at the right for n = 6. The group operation is multiplication of complex numbers. In the picture, multiplying with z corresponds to a counter-clockwise rotation by 60. Using some field theory, the group Fp can be shown to be cyclic: for example, if p = 5, 3 is a generator since 31 = 3, 32 = 9 4, 33 2, and 34 1.

What is a group labeled when the element 1 is primitive?
Output: cyclic

Input: Tucson, Arizona
Interstate 10, which runs southeast to northwest through town, connects Tucson to Phoenix to the northwest on the way to its western terminus in Santa Monica, California, and to Las Cruces, New Mexico and El Paso, Texas toward its eastern terminus in Jacksonville, Florida. I-19 runs south from Tucson toward Nogales and the U.S.-Mexico border. I-19 is the only Interstate highway that uses "kilometer posts" instead of "mileposts", although the speed limits are marked in miles per hour instead of kilometers per hour.

Which interstate is the only one that uses kilometer posts instead of mileposts?
Output: I-19

Input: IPod
On April 9, 2007, it was announced that Apple had sold its one-hundred millionth iPod, making it the biggest selling digital music player of all time. In April 2007, Apple reported second quarter revenue of US$5.2 billion, of which 32% was made from iPod sales. Apple and several industry analysts suggest that iPod users are likely to purchase other Apple products such as Mac computers.

As of 2007, what percentage of Apple's revenue came from iPod sales?
Output:
32%