City sources predict the FTSE 100 will open up 12 points from yesterday's close of 5,451 after Monday's declines, which saw the index drop 63 points on the back of comments made by German Chancellor Angela Merkel, who underlined her opposition to the issuing of common euro area bonds. International outsourcing firm Serco said it was on track for 2012 but expects revenues in the first half to take a hit from tough conditions in America. In a statement ahead of the firm's half year end, Serco said it expected strong total revenue growth in 2012, including good organic growth. But it forecast that adjusted operating margins would be flat in the first half compared to the corresponding period in 2011.Oil and gas services provider Petrofac has again reiterated its full-year profit guidance, saying that both its Engineering, Construction, Operations and Maintenance (ECOM) and Integrated Energy Services (IES) divisions are making good progress. The company expects net profits to grow by at least 15% in 2012, unchanged from its guidance in May. Based on the contracts signed in the year so far, Petrofac's expects its backlog to be around $9.1bn by the end of the first half (June 30th), down slightly from $10.8bn at the start of the year. FTSE 250 chemicals group Elementis has agreed to buy Brazilian coatings additives company Watercryl Quimica for a cash consideration of £24m. "This acquisition represents significant progress in extending our reach into the fast growing and increasingly sophisticated Latin America coatings market," said Chief Executive David Dutro.