In a Recent Survey of Stars in the Sky,it Was

question 90

Multiple Choice

In a recent survey of stars in the sky,it was found that occasionally a star that is normally of constant brightness will slowly brighten and then fade back to its original brightness again over the space of several weeks.What is believed to be the cause of this change in brightness?

• A) a massive coronal ejection on a star with abnormally strong magnetic fields
• B) the gradual motion of the star through a break or hole between interstellar dust clouds
• C) microlensing by compact objects such as brown dwarfs passing in front of the star
• D) the "lighthouse beam" of a slowly rotating neutron star companion

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Definitions:

Liabilities

Financial obligations or debts that a company or individual owes to others, which must be paid back in the future.

Government Securities

Financial instruments issued by the government to borrow money from the public.

Excess Reserves

The amounts of cash banks hold in reserve over and above the regulatory requirements, which can influence their capacity for lending and overall liquidity in the economy.

Required Reserves

Required Reserves refer to the minimum reserve of cash that banks must hold either in their vaults or on deposit with the central bank, as mandated by financial regulations.