Energy Conservation - It is estimated that only a 40-year reserve of oil remains in the earth

OFFICIAL FIRST DAY OF ISSUE 20 ENERGY CONSERVATION IT IS ESTIMATED THAT ONLY A 40 YEAR RESERVE OF OIL REMAINS IN THE EARTH Art Craft бета, 'W' SEP 23 1974 48233 EN ER HY CONSERVATION TIMME 10+ FIRST DAY OF ISSUE