Creating excel function/formula to automatically calculate aggregate median, range, and studies.

Hello,

I would like to seek your support to answer another query if possible. The excel community's support has been extremely helpful to making it more efficient and really fascinating to learn the several functionality of excel! 

My question is that I would like to create excel formula/equations/functions to automatically draw the median enrollment rates, range, and number of studies for each country. Each of these needs to be further filtered based on the Data Source 1 and Data Source 2 as indicated within the excel file. 

I have attached a sample excel example in attached and filled in the answers in the green cell.

Thank you kindly,

Amy