On what is set to be one of the busiest days of the year for big company announcements London is poised to open moderately firmer, with the FTSE 100 index tipped by City traders to open around 14 points higher.Banking giant Barclays reported a 44% rise in first half pre-tax profits as profits at the lender's investment banking arm, Barclays Capital, more than trebled, though that was partially offset by an increase in impairments in Barclays Corporate in Spain. Pre-tax profit rose to £3,947m in the first half of 2010 compared with £2,745m last time. Excluding movements on own credit, gains on acquisitions and gains on debt buy-backs, pre-tax profit increased by 22% to £2,963m.RSA Insurance Group reported revenue growth in all geographic regions and a 'resilient underwriting result' in what was a tough first half for the insurance industry. Net written premiums in the first six months of 2010 rose 9% (6% at constant exchange rates) to £3.80bn from £3.49bn in the first half of 2009. Pre-tax profit was virtually flat at £302m.Defence and aerospace products group Cobham saw pre-tax profits fall in the half year to June 30 as it suffered from weakness in some of its commercial operations and delays in defence contracts. Pre-tax profits for the period totalled £97m, down from £139m the previous year, even as total revenues increased to £963m from £952m.Fresh from its apparent success plugging the leaking Maconda well in the Gulf of Mexico with mud, oil giant BP has been given clearance to start the cementing part of its 'static kill' process.