How do Painkillers Work?
We sense pain due to the transmission of a specific signal to the brain via the spinal cord. Pain relief medications work by preventing this 'pain signal' from reaching the brain. There are two main types of painkillers that are commonly used: the 'aspirin medicines' and the 'narcotic medicines.' The Aspirin-type painkillers block the body's prostaglandins - molecules responsible for pain and swelling. Blocking prostaglandins blocks the signal at the source of the pain, as well as reducing swelling. The Narcotic-type medicines block the pain messages in the spinal cord and the brain, and are typically used for much more severe pain relief. Each group of painkiller is comprised of numerous sub-types, each with slightly different modes of action. This can allow certain pain relief medicines to be combined safely.
The county cleared this path and paved it with packed gravel, so they would have a peaceful place to hike and bike. Which of the following alternatives to the underlined portion would NOT be acceptable? path, paving path and then paved path before paving path paved
To find the unacceptable alternative, let’s first figure out the meaning of the original sentence. Two things happened: first the county cleared the path, and then the county paved it. So any answer choices that express this sequence of events would fit the sentence, and thus not be the "wrong" answer that we are looking for here. Answers A, B, and C all express the same idea in slightly different ways, creating perfectly grammatical phrases. Now let’s see what happens when we plug in answer J. We get this weird sentence: “The county cleared this path paved it with packed gravel…” This is clearly a run-on sentence, so answer D is our odd man out.
How do magnets work ?
Magnetism is a property of materials that makes them experience a force in a magnetic field. But what makes a metal magnetic? It is all down to unpaired electrons: moving electrons create magnetism due to their magnetic charge, but in most atoms electrons are paired and so cancel each other out.