We have two problems with change of units.
Here we know that with one tea bag we can make 180 ml of tea, rewriting this in liters, we need to use that:
1 ml = 10^-3 L
180 ml = 180*(10^-3 L) = 0.18 L
Now we also know that in one box we have 24 teabags, the total amount of tea that we can make is:
24*0.18 L = 4.32 L
First, he dug 4,5 meters, and then he dugs another 120cm.
Using that:
1m = 100cm
We can rewrite:
120 cm = (120/100) m = 1.2m
Then the total amount that he dug is:
4.5m + 1.2m = 5.7m
Then we know that the water in the hole is 230cm deep, writing this in meters we have:
230 cm = 230/100 m = 2.3m
Then the part of the well that is not filled with water is given by:
5.7 m - 2.3m = 3.4m
This means that 3.4 meters of the well are not filled with water.
If you want to learn more about changes of units, you can read:
https://brainly.com/question/11324103