Question

Complete as frases abaixo com o present perfect dos verbos entre parênteses a) STUDIES SHOW THAT SOLAR VARIABILITY (PLAY) A ROLE IN PAST CLIMATE CHANGES b) THERE'S A MORE THAN 90 PERCENT PROBABILITY THAT HUMAN PRODUCED GREENHOUSE GASES (CAUSE) MUCH OF THE OBSERVED INCREASE IN EARTH'S TEMPERATURES OVER THE PAST 50 YEARS

Answer 1

a) STUDIES SHOW THAT SOLAR VARIABILITY HAS PLAYED A ROLE IN PAST CLIMATE CHANGES

b) THERE'S A MORE THAN 90 PERCENT PROBABILITY THAT HUMAN PRODUCED GREENHOUSE GASES HAVE CAUSED MUCH OF THE OBSERVED INCREASE IN EARTH'S TEMPERATURES OVER THE PAST 50 YEARS