The rating on Newark Unified School District, Calif.'s bonds reflects: Participation in the San Francisco Bay Area's strong and diverse economy; Above-average income and wealth; and A large and steadily growing property tax base. These strengths are somewhat offset by moderate yet growing debt levels and slow amortization. The district encompasses 13 square miles in southwestern Alameda County, serving the city of Newark, 35 miles southeast of San Francisco. The city (population 40,500) and the district are coterminous. The district is predominantly residential and largely built-out. Student average daily attendance, currently 7,326, is projected to continue to grow modestly through 2001. Newark's economic base has diversified and features manufacturing, retail trade, and services. In addition to the district, leading employers