The Iowa Economic Development Authority approved an additional $300,000 in tax credits Friday for General Mills’ $57 million expansion in Cedar Rapids.The project, which will add a new manufacturing line and 60 jobs, initially was supposed to cost $37 million and received $765,000 in state tax credits in August. The Minneapolis-based food manufacturer then increased the budget for machinery and equipment, from $30 million to $50 million.The expansion comes with additional 10 jobs with average wages between $23.49 and $29.62 per hour.