Roho safi ,Tanzania needs to do something about your English curriculum.
There is a difference between 'the poorest', and 'one of the poorest'.
You sound very naive in things.
Very few countries in the world have a $1 Trillion+ GDP. Even fewer have a $ 1 Trillion + annual budget.
Tanzania may have a $Trillion buried in the ground, but that does not make it wealthy. At your current pace, it will take you 1000 years to exploit your resources, and hence you will remain one of the poorest countries on earth.
Tanzania cannot afford Jets. It is spending money meant for other things to feed the ego of Magufuli.
Here in Nairobi we have recently built a very important, brand new highway, (outering road), that will open up the entire Eastlands as well as be used by tens of thousands of cars daily. Possibly millions of passengers a year.
And all that for half the cost of a single dreamliner.
Tanzania on the other hand, with one of the poorest road connectivity in the region, with 32% electricity connection, with millions living below the poverty line, with few or no cancer machines, etc.. decides to buy dreamliners to carry 200 people a day.