Which is a property of potassium (K)? A. It is dull and brittle.
B. It is extremely reactive.
C. It is not reactive.
D. It is white and hard.

B: It is extremely reactive

Explanation:

Potassium metal is also soft and white with a silvery lustre, has a low melting point, and is a good conductor of heat and electricity.

Properties, occurrence, and uses. Potassium metal is soft and white with a silvery lustre, has a low melting point, and is a good conductor of heat and electricity. Potassium imparts a lavender colour to a flame, and its vapour is green.

Explanation: hope it helps

a small container that holds a source of energy a solar cell that captures light energy and converts it into electricity a voltaic cell that uses the oxidation of a fuel to produce electricity

explanation:

geosphere and hydrosphere.

this is because the geosphere has to do with geological events, while the hydrosphere controls all water on earth.