Can someone me with this question

in what direction do particles naturally diffuse?

question 8 options:

up concentration gradients

down concentration gradients

across concentration gradients

through concentration gradients

How do water’s relative densities as a solid and a liquid differ from that of most other substances? water’s solid and liquid forms have different densities, while most other substances have solid and liquid forms with similar densities. water’s solid and liquid forms have similar densities, while most other substances have solid and liquid forms with different densities. water’s liquid form is less dense than its solid form, while the opposite is true of most other substances. water’s solid form is less dense than its liquid form, while the opposite is true of most other substances.

Which of the following is the sl unit used to measure temperature a. kilogram b. liter c. meter d. kelvin

Which of the following are responsible for sending messages from the hypothalamus to the thalamus?