added our powerpoint to the github
added our powerpoint to the github


Former-commit-id: 9f90abdd25ecc7a4e243431268b88d69357c8dcf
Former-commit-id: 8217f129a73f6399ff75b6f4442329d1172e0ab8
dssg/wikienergy,dssg/wikienergy,dssg/wikienergy,dssg/wikienergy,dssg/wikienergy