In a survey conducted in a town, the number of children in the houses is given below:
| Families | Number of children |
| More than or equal to 1200 | 10 |
| More than or equal to 2400 | 6 |
| More than or equal to 3600 | 3 |
| More than or equal to 4800 | 1 |
| More than or equal to 6000 | 0 |
1. The lower limit of the median class is _________.
2. The upper limit of the median class is __________.
3. The median is ___________.
4. The construction of cumulative distribution table is useful in determining the ____________.
5. Which family group have the maximum number of children?