Chang Liu@cliu8421United StatesFollow BadgesProblem Solving CertificationsCertificate: Problem Solving (Basic)VerifiedskillCertificate: Problem Solving (Intermediate)VerifiedskillCertificate: Problem Solving (Advanced)VerifiedskillWork Experiencecliu8421 has not updated employment details yet.Educationcliu8421 has not updated education details yet.