Fast I will give branliest

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Explanation:

It takes 3 different vibrations to hear a sound, since sound is made when things vibrate (or wiggle) : The object that makes the noise vibrates (our bell). The air molecules vibrate as the sound moves through the air. The eardrum vibrates when the sound wave reaches it

Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.

the sugar-phosphate backbone forms the structural framework of nucleic acids, including dna and rna. this backbone is composed of alternating sugar and phosphate groups, and defines directionality of the molecule.

desert perennials often survive by remaining dormant during dry periods of the year, then springing to life when water becomes available. most annual desert plants germinate only after heavy seasonal rain, then complete their reproductive cycle very quickly.