Questions

The error is in first part. ‘Considering’ is a preposition that relates the facts to the principal and hence does not need to be followed by another preposition ‘about’. A preposition like ‘considering’ should be followed by a pronoun like ‘these’ in this case. The use of about is unnecessary and shall be omitted. The sentence indicates that the principal offered him a seat only after considering certain facts.

The Kyoto Protocol is an international agreement linked to the United Nations Framework Convention on Climate Change, which commits its Parties by setting internationally binding emission reduction targets.

Recognizing that developed countries are principally responsible for the current high levels of GHG emissions in the atmosphere as a result of more than 150 years of industrial activity, the Protocol places a heavier burden on developed nations under the principle of "common but differentiated responsibilities."