Which of the following characteristics apply mainly to invertebrates? (Choose all that apply.)
A.) many different body plans that display all types of symmetry
b.) backbone and inner skeletal structure
c.)lack of skeletal structure in their bodies
d.)limited to no development of organ systems

c and d

Explanation:

because they are cold blooded n have no back bone

the answer is:

carbon dioxide

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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.