Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Class | Part 1 | Part 2 | Part 3 | Part 4 | Verb meaning |
| --- | --- | --- | --- | --- | --- |
| 1 | rītan | reit | ritun | giritan | to ride |
| 2a | friosan | frōs | frurun | gifroran | to freeze |
| 2b | sūfan | souf | sufun | gisoffan | to close |
| 3a | bintan | bant | buntun | buntan | to bind |
| 3b | werdan | ward | wurtun | giwortan | to become |
| 4 | beran | bar | bārun | giboran | to bear |
| 5 | lesan | las | lārun | gileran | to gather, to read |
| 6 | tragan | truog | truogun | gitragan | to carry |
| 7a | heizan | hiaz | hiazun | giheizan | to call, to be called |
| 7b | (h)loufan | (h)liof | (h)liofun | gi(h)loufan | to run |
| 7c | haltan | hialt | hialtun | gihaltan | to hold |
| 7d | rātan | riat | riatun | girātan | to advise |
Question:
What class in the word with part 4 "giheizan"?
Answer:
7a