WASHINGTON (AP) - The nation's unemployment rate is now at a four and a-half-year low of 7.4 percent. The Labor Department says the rate fell from 7.6 percent in June. But otherwise, today's jobs report isn't as bright. Employers added 162,000 jobs in July -- the fewest since March. And fewer jobs were added in the previous two months than had been estimated. Also, Americans worked fewer hours, and their pay dipped -- suggesting that weak economic growth may be making businesses cautious about hiring.