a$)$ The selected companies are: $[\text{'}$GSK$\text{'},$'HSBA',$\text{'}$BP$\text{'},$'AZN','BARC','VOD','DGE',$\text{'}$RR$\text{'},$'TSCO','LLOY' 'IMB','PRU',$\text{'}$AV$\text{'},$'GLEN',$\text{'}$NG$\text{'},\text{'}$BA$\text{'},\text{'}$WPP$\text{'},$ 'INF','WIZZ','STAN'$]$

b$)$ By using Yahoo Finance API

For $6$ months back retrieve stock prices for all selected companies

Organize data to the following table.