What Makes Us Think That Mars Must Once Have Had

question 173

Multiple Choice

What makes us think that Mars must once have had an atmosphere that was warmer and had higher surface pressure?

• A)We think it for purely theoretical reasons, based on calculations showing that the Sun has brightened with time.
• B)The fact that parts of Mars have a lot of craters tell us that Mars must once have been much warmer.
• C)The atmosphere is too cold and thin for liquid water today, yet we see evidence that water flowed on the surface in the past.
• D)The presence of inactive volcanoes on Mars tells us that there must once have been a lot of outgassing, and hence a thicker atmosphere.

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General Partner

A full partner with unlimited liability for the debts of the partnership.

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A partnership consisting of at least one general partner, who manages the business and is personally liable for debts, and one or more limited partners, who invest but do not participate in management.

Partnership Interest

The share or portion of a partnership owned by one of the partners, including rights to its profits.

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The ability of an entity or individual to enter into legally binding contracts and to sue or be sued.