Assume that the current corporate bond yield curve is upward sloping, or normal. Under this condition, we could be sure that a.Long-term interest rates are more volatile than short-term rates. b.Inflation is expected to decline in the future. c.The economy is not in a recession. d.Long-term bonds are a better buy than short-term bonds. e.Maturity risk premiums could help to explain the yield curve's upward slope