Which of the following was a reason for entrance of the united states into world war 1? a. the united states wanted to ensure a new nation for the polish people b. the united states got pulled into the war through its alliance with france c. the german use of unrestricted tank warfare d. the german use of unrestricted submarine warfare

Hey there! The answer you are wanting is "The German use of unrestricted submarine warfare" or option D. 

The Germans also tried to get Mexico to form an alliance with them against the United States! So you can definitely see the problem! 

Hope this helps you out!!

May consider a group  g=({0,1},+)g=({0,1},+)where  ++  will work as the xor operator like we work in boolean algebra. note here, that ‘00’ and ‘11’ are not the usual 0 and 1 that we work with everyday. the elements are  called  ‘00’ and ‘11’ and  may not mean  zero (nothing) and one (single). ‘00’ is the identity for the given binary operator +, meaning that any element operated with ‘00’ gets us that element itself.  for a set  ss  in  g′g′  having more elements than just  {0,1}{0,1}  the values for  a+b∈sa+b∈s, such that  a∈s,b∈sa∈s,b∈s, have to be first defined, only then can you determine the value of  1+11+1. the answer could possibly have been  22  if oanswer is25,000