Answer:
d. smooth endoplasmic reticulum
Explanation:
Organelles are structures found in inside the cell which carries out a specific function. Types of organelles include endoplasmic reticulum, Golgi body, ribosomes, nucleus etc. The function in the question is protein synthesis. 
Ribosomes are the sites of protein synthesis in the cell of living organisms. 
- The nucleus is involved in the synthesis of protein because it directs all the cellular processes in a cell including protein synthesis.
- Rough endoplasmic reticulum (RER) is a type of endoplasmic reticulum whose surface is attached to by ribosomes, hence, giving it its rough surface. Since ribosomes (organelle for protein synthesis) are attached to the RER, the RER are involved in protein synthesis. 
- Golgi bodies are organelles that functions to package, process and sorted the proteins produced in the ribosomes. 
- The smooth endoplasmic reticulum (SER) are NOT involved in the synthesis of protein because they have no ribosomes attached to their surface. Instead, they are involved in lipid synthesis.
 
        
             
        
        
        
Answer:Use a stretched Slinky to model sound waves moving through a material.When you squeeze the Slinky's coils together at one end (compression), this causes the coils in front of them to spread out (expansion). When the squeezed coils are released they spread out and squeeze the coils in front of them together. The squeezed coils in turn move forward, pushing on the coils in front of them and so on.
Squeezing the end coils gave them energy that was transferred from one end of the slinky to the other. As the energy goes through the Slinky, all the coils do not move at once, some of the coils are crowded together and some are spread apart.
 
        
             
        
        
        
<u><em>Atomic Number. I hope that's what you were asking.</em></u>