In 1977, Mario and Clara, both Filipino citizens, were married in the Philippines. Three years later, they went to the United States of America and established their residence in San Francisco, California. In 1987, the couple applied for, and were granted, U.S. citizenship. In 1989, Mario, claiming to have been abandoned by Clara, was able to secure a decree of divorce in Reno, Nevada, U.S.A. In 1990, Mario returned to the Philippines and married Juana who knew well Mario's past life. (a)Is the marriage between Mario and Juana valid? (b)Discuss the procedure and requirements in filing a Petition for Recognition of Divorce Decree