Some kids are playing with a jump rope. They notice that they can make transverse waves when they shake the rope up and down. They shake it quickly and notice that the wave that forms appears to be holding still. What type of wave interaction is this?

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

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since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

im pretty sure its b

d : a person who learns about the world by observing it. no that is not a smiley face

explanation: