Suppose We Observe a Source of X-Rays That Varies Substantially

question 38

Multiple Choice

Suppose we observe a source of X-rays that varies substantially in brightness over a period of a few days.What can we conclude?

• A)The X-ray source is a quasar.
• B)The X-ray source contains a black hole with an accretion disk.
• C)The X-ray source is no more than a few light-days in diameter.
• D)The X-ray source must have a strong,rapidly varying magnetic field.

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Definitions:

European Call Option

A financial contract that gives the buyer the right, but not the obligation, to buy an underlying asset at a set price on a specific expiration date, only exercisable at the end of its term.

Expiration Date

The specific date upon which an options or futures contract becomes void and the holder must execute or relinquish the contract.

Exercise Price

The specified price at which the holder of an option can buy (call) or sell (put) the underlying asset.

Stock Splits

A corporate action that increases the number of a company's outstanding shares by dividing each share, which typically reduces its share price but does not affect the company's overall market capitalization.