periodic-changes
| Topic | Replies | Views | Activity | |
|---|---|---|---|---|
| Explain the following terms with example 1)periodic change 2)desirable change |
|
1 | 292 | July 17, 2019 |
| What are periodic changes? |
|
1 | 245 | June 25, 2019 |
| What are periodic and non-periodic changes? |
|
1 | 325 | June 19, 2019 |