SAO PAULO, 17 April (Reuters) – Raw steel output in Brazil rose 6.6 % to 2.944 million tonnes in March in an annual basis, Aco Brasil, the group that represents mills, said on Thursday. Sales in the local market rose 10.7 % to 1.880 million tonnes in the March from the same period a year earlier,the institute, known as Aço Brasil, said in a report.