The following table shows population (in lakhs) of different cities.
| Cities | 2018 | 2019 | 2020 |
| Bangalore | 25 | 31 | 37 |
| Jalandhar | 15 | 18 | 25 |
| Jaipur | 11 | 13 | 17 |
| Mumbai | 33 | 43 | 52 |
| Delhi | 29 | 35 | 42 |
What is the average population (in lakhs) of all the cities in the year 2019?
1
21
2
28
3
31
4
33