We wanted to know if the length of time food is in contact with a contaminated surface affected the rate of transfer of bacteria to the food.

我们想知道食物与被污染的表面接触的时间长短是否会影响细菌转移到食物上的速度。

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The culprit may be weak back muscles, the type of surface on which you run, the shoes you wear, or the length of your running stride.

其原因可能是背部肌肉太弱，也可能是你奔跑的路面有问题，还可能是你穿的鞋不合适，也许是因为你的步幅不对。

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Long and thin, this moon measures about 90 feet in length, and its uneven surface is rife with craters.

这颗卫星又细又长，长度大约在90英里(约合144公里)左右，其表面并不平坦，布满陨坑。

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Airships demonstrate a law of increasing returns: doubling the length increases the surface area (and hence weight) by a factor of four while the volume (and hence lifting capacity) goes up by a factor of eight.

ECONOMIST: Pushing the envelope

After some experimenting, Norton settled on growing tin in the form of needles (about 50 nanometers in length) and adding textures to the material to create more surface area.

FORBES: Tin: The Secret To Improving Lithium-Ion Battery Life

"If it works well, the keyboard -- which I got to inspect at great length but not actually type on -- is going to be the Surface's killer attraction, " wrote Slate's Farhad Manjoo.

CNN: 5 ways Microsoft's Surface may be better than an iPad