Why are sunspots dark? A) They are cooler than the surrounding gases.
B) They are areas of solid material on the sun.
C) They are warmer than the surrounding gases.
D) They are old spots on the sun.

A) They are cooler than the surrounding gases.

Explanation:

Sunspots are dark, planet-sized regions that appear on the "surface" of the Sun. Sunspots are "dark" because they are cooler than their surroundings.

A

Explanation: the gas inside the spot where the magnetic field is strongest is only emitting about 1/4 as much light as from the rest of the solar surface

characterization of nanoparticles is a critical step in nanomaterial production as it provides information of dimension, morphology, surface charge, distribution and degree of surface functionalization.

when atoms of different types of elements join together, they make molecules called compounds. water consists of compound molecules made up of 2 hydrogen atoms and 1 oxygen atom. this is why it's called h2o. water will always have 2 times the number of hydrogen atoms as oxygen atoms.