Evidence of tolerance  1) It was not until 1979 that a non-standard surcharge was put on First-Class Mail, and even now it applies only to the first ounce.
Sending First-Class mail cost less back in 1978.
mnli hypothesis: Sending First-Class mail cost less back in 1978. premise: Evidence of tolerance  1) It was not until 1979 that a non-standard surcharge was put on First-Class Mail, and even now it applies only to the first ounce.