Answer:
I will research on troposphere Because:-
1. Most of phenomena occurs in troposphere
2. Most of terrain is found in troposphere
3. It is first layer of atmosphere
4. It is the nearest layer of atmosphere from the surface of earth
5. As it contain most of things so there most chance of discovering a new undiscovered thing
Explanation:
Hope this help!!
I would Say C. Water I’m not sure but that’s my best guess
Answer:
Spain by "then" will be a depopulated nation dominated by elderly and single people,the country will have lost 5.3million inhabitants, or 11% of the current population, by the middle of the century. If the trends continue, by then the over 65s will make up 34.6% of the population while close to a quarter of a million Spaniards will be over 100yrs old.By that date there will be 1.7million fewer children under 10 than there are now.....