1. B
2. H
3. G
4. I
5. D
6. C
7. A
8. F
9. E
I am not sure weather it is correct but I wrote what I know
I am sure the answer is D
Answer:
help with problem 4
Explanation:
4. protons are equal to atomic numbers. neutrons are atomic mass minus atomic number. electrons are equal to protons.
5. I don't know, sorry.
Concave is not a type of mechanical wave because it doesn’t need a medium for propagation.
