The initial discovery of the need for an International Date Line is MOST LIKELY credited to the crew of which European explorer?

I uploaded the answer to a file hosting. Here's link:

tinyurl.com/wpazsebu

john maynrd keynes developed new economic respose to the                           ( b. great depression if the 1930's)

as the person below or above me i agree   the tone of voice of the itnerview can very well influecne he or she to pick one more over that   the infleuncer would pick