Fed Chair Powell Says Inflation Elevated, In Part Reflecting Energy Price Increase; Current Policy Stance Appropriate; Promotes Progress Toward Goals; Middle East Events Contributes To Uncertainty; Risks To Both Sides Of Mandate; Consumer Spending Resilient; Unemployment Rate Has Changed Little; Job Growth Slowing Reflects Slower Labor Force Growth; Labor Demand Has Softened; Labor Demand Has Also Softened Clearly; Sees PCE At 3.5% In March