Optical and radio astronomy are the oldest and best established branches of astronomy, but since the 1970s there has been a virtual explosion of observational techniques covering the rest of the electromagnetic spectrum. Today, all portions of the spectrum are studied, from radio waves to gamma rays, to maximize the amount of information available about astronomical objects. As noted earlier, the types of astronomical objects that can be observed may differ markedly from one wavelength range to another. Full spectrum coverage is essential not only to see things more clearly, but even to see some things at all.
a. In order to observe astronomical objects astronomers must use techniques that allow full spectrum coverage.
b. Optical and radio astronomy are the oldest and best established branches of astronomy, but with modern technology other branches are rapidly developing.
c. Optical and radio astronomy have been the leading branches of astronomy since the 1970s and will probably remain so into the 21st century.
d. Since there are such differences in types of astronomical objects in different wavelengths, many are not observed at all.
Question 2
All governments tax, penalize, punish, restrict, and regulate their people. Governments in the United States the federal government in Washington, the 50 state governments, and the more than 86,000 local governments take nearly 40 cents out of every dollar Americans earn. Each year, the congress enacts about 500 laws; federal bureaucracies publish about 19,000 rules and regulations; the state legislatures enact about 25,000 laws; and cities, counties, school districts, and other local governments enact countless local ordinances. Each of these laws restricts our freedom in some way. Each dollar taken out of our wages or profits reduces our freedom to choose what to do with our money.
a. There are many laws and regulations that attempt to govern our lives in ways that may sometimes penalize, punish, or regulate the people they should protect.
b. All laws are designed to restrict our freedom; however, many of the laws enacted are not enforced.
c. Each dollar taken out of our income by the local, state, and federal governments reduces our freedom to choose what to do with our money.
d. Our local, state, and federal governments take nearly 40 percent of our income, enact laws, publish rules and regulations, and issue ordinances that restrict our freedom in some way.
Optical biopsy.
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