The Lack of Large Impact Craters on the Surface of Europa

question 47

Multiple Choice

The lack of large impact craters on the surface of Europa is consistent with

• A) active volcanism that is constantly resurfacing the crust
• B) the surface being covered with an ocean of liquid water
• C) the crust being so thick and hard that impacts leave no marks on the surface
• D) a subsurface ocean of water because large impacts will break the thin crust causing water and slushy ice below to flood out and resurface the crust

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Definitions:

Blood Calcium

refers to the level of calcium in the blood, essential for bone health, muscle function, and nerve signaling.

mEq/L

Milliequivalents per liter, a unit of measurement in chemistry and medicine indicating the concentration of ions in a solution.

Sodium Blood Level

The concentration of sodium in the blood, essential for maintaining blood pressure and proper functioning of muscles and nerves.

mEq/L

Milliequivalents per liter, a unit of concentration used in chemistry and medicine to express the amount of a substance in a liquid.