Liberia, in west africa, is not associated with a european power on this map. what is the reason for this?

I can't see the map, but I think I can answer the question anyway. Liberia was special in that it wasn't a typical colony of an European country: it wasn't established with a thought of integrating it into the country or extracting resources from it, as with the other colonies. Instead, it was thought of as a country for black people: freed slaves from the US.

This is all you, but i can give you some topics that you could try. if it rained when you want to do something outdoors, it 'limits' that human activity. maybe you want to do an experiment that goes throughout the whole year and you have to have above freezing the entire year. this 'limits' your activity. i thought of those just off of the top of my head. something that gets to me that might be getting to you is you are thinking too hard about what to do. think simply, and if it is too simple, then bump it up just a little bit.

Magma forms by partial melting of upper mantle and crust. partial melt means that only a fraction of the available material forms a melt, and that the remainder stays solid. the partial melt rises because of its lower density and ascends through he crust. this is so conclusive mean the answer would be magma igneous rocks or balistic magma.