Given a scientific passage and an answer, generate a question for the given answer.

Q: Passage: Amines are weak bases due to the presence of a lone pair of electrons on the nitrogen atom. This lone pair can attract the hydrogen atom from a water molecule, causing the bond between it and the oxygen atom to break. The resultant products are the conjugate acid of the amine and the hydroxide ion. Answer: electrons

A: Amines are weak bases due to the presence of a lone pair of what on the nitrogen atom?
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Q: Passage: The electron cloud of a helium atom contains two electrons, which can normally be expected to be equally distributed spatially around the nucleus. However, at any given moment the electron distribution may be uneven, resulting in an instantaneous dipole. This weak and temporary dipole subsequently influences neighboring helium atoms through electrostatic attraction and repulsion. It induces a dipole on nearby helium atoms (see Figure below ). Answer: an instantaneous dipole

A: A weak and temporary dipole that influences nearby atoms through electrostatic attraction and repulsion is known as what?
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Q: Passage: Cardiac muscle also contracts and gets shorter. This muscle is found only in the heart. The sudden burst of contraction forces blood throughout your body. When the cardiac muscle relaxes, the heart fills with blood. This rhythmic contraction must continue for your whole life, luckily the heart muscle never gets tired. If your heart beats 75 times a minute, how many times does it beat in an hour? A day? A year? 85 years?. Answer: heart

A:
Cardiac muscle is only found where?
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