Ans:
| a) | Serial_no. | Invalid | We cannot use any punctuation mark in identifier name |
| b) | 1st_Room | Invalid | Variable name cannot begin with number |
| c) | Hundred$ | Valid | We can use ‘$‘anywhere in variable name except at the beginning. |
| d) | Total Marks | Invalid | We cannot provide space between the names of variable. |
| e) | Total_Marks | Valid | We can use ‘_’ anywhere in variable name. |
| f) | total-Mark | Invalid | We cannot use ‘-‘ in variable name as it is treated as system defined identifier. |
| g) | _Percentage | Valid | A variable name can begin with ‘_’. |
| h) | True | Invalid | System defined identifier |