As discussed in the chapter opening vignette and on page 9, companies are increasingly issuing reports on corporate social responsibility. Visit the Global Reporting Initiative Web site (www.globalreporting.org) and answer the following questions. a. What is the vision and mission of the Global Reporting Initiative? b. What is a sustainability report? Explain the use of sustainability reports in integrated reporting. c. Explain the two in accordance GRI guideline reporting options. What is the GRI guidance on assurance for in accordance reports?