Many cat species mark their territory by rubbing glands on their faces against a surface such as a tree trunk. this form of communication relies on a

a. visual signal.

b. sound signal.

c. chemical messenger.

d. defensive display.

yes? sounds right, but you didn’t ask a question.

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what do the different brain waves do?

explanation:

brainwaves are produced by synchronised electrical pulses from masses of neurons communicating with each other. brainwaves are detected using sensors placed on the scalp. brainwave speed is measured in hertz (cycles per second) and they are divided into bands delineating slow, moderate, and fast waves.