Answer:
I'm pretty sure it's called erosion.
Explanation:
Bursa - A small sac that lubricates the area around a joint where friction is most likely to occur
ex. elbow, knee, or shoulder
Answer:
A sexual reproduction is being shown
When coming to building something, some materials are more vulnerable to water and can wear away easier. Some can keep the water in, so depending on the material, the water quality can be better sustained.
