Which Combination of Optics Is Used in the Schmidt-Cassegrain Telescope

question 80

Multiple Choice

Which combination of optics is used in the Schmidt-Cassegrain telescope for producing high-quality wide-angle images of the sky?

• A) single, short-focal-length spherical mirror
• B) parabolic mirror of short focal length, used at prime focus
• C) two lenses of different glass, one convex, the other concave, to reduce chromatic aberration
• D) spherical primary mirror with a thin correcting lens ahead of it

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Definitions:

Contribution Margin Ratio

The percentage of each sale that remains after variable costs are deducted, indicating how much revenue is contributing to fixed costs and profit.

Operating Leverage

A measure of how sensitive a company's operating income is to a change in sales, reflecting the proportion of fixed costs in the company's cost structure.

Break-even Point

The point where the amount of goods produced or sold matches the total expenses, leading to neither a profit nor a loss.

Contribution Margin

The difference between sales revenue and variable costs, used to cover fixed costs and to generate profit.