The CMB data suggests that the Universe is flat with in 0.4%. CMB data also shows that the expansion of the Universe is accelerating (from the sum of angles of triangle formed by distant hot spots- Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess). The pushing out dark energy is about 74% of the energy/mass of the Universe. Question - (a) is 74% dark- 26% dark+real matter arrived from the experimental results of observed expansion acceleration to give a flat Universe? (b) If the expansion is accelerating, what does it mean for the curvature - should it have a slight negative curvature from FLRW equations? If the Universe is flat and infinite, why do people (like Roger Penrose) continue to talk about big bang- big crunch cycles?