News roundup: US economy grew at brisk 4.2% rate in Q2 … Americans’ pessimism on economy has grown … St. John the Baptist Parish purging water system after amoeba found

Beating expectations: After a bleak start to the year, the U.S. economy grew at a brisk annual rate of 4.2% in the April-June quarter, the government reports today, slightly faster than it had first e…