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When you mate two plants together the terms is called? answer it fast as possible plz! i have a test tomorrow!

Astudent carefully transfers 30 g of water and 30 g of alcohol in a glass tube, forming two layers and filling the tube completely. after sealing the tube, the student mixes the solutions, and notices a bubble that forms in the tube. what is the mass of the contents in the glass tube after mixing?

Calculate the frequency of a wave in a spring toy. the wave has a speed of 1.1 meters per second and a wavelength of 0.1 meters. *