During schedule and cost control, when comparing performance to the schedule and cost baselines, if schedule or budget has changed these changes should be: 1) formally recommended and managed through the integrated change control system. 2) added to the original baselines, and baseline changes made to reflect the new status. 3) reviewed with the customer or sponsor to obtain approval for additional funding. 4) implemented immediately and reported as variances from baseline in the next status report.In which of the following tools would a normal or bell-shaped curve be expected if no special conditions are occurring? 1) flow chart 2) cause and effect diagram 3) check sheet 4) histogram