[varia] can't expand settlement

1. I have had 3 master expanders (for about 2 months now) but still only five plots. how long does it take to expand? is it a bug?

2. how many citizens can one food garden feed? will having more than one food geatherer per garden increase the food output? what is the calculation?

3. I can hire only 10 troops in the settlement, any way to increase this number ?

4. why does the numebr of arrows diminish/use up only sometimes? what triggers it?

I don't remember the formulas for 1, 2 and 3 
I will look into it.
Arrows are replenished to the multiple of 5 immediately above. for example, if you have 12 arrows left at the end of the battle, you will start a new battle with 15. If you had 26, it would be 30. This code was very difficult to create, is very messy, easily bugged