"Ouagadougou" should be accepted for the first question. The answer to "What is 1 half multiplied by one half?" should have a slash (/) instead of a backslash (\). Moreover, it would be good if "1 quarter" and "one quarter" were accepted for that question. These are not the only problems; the question "What is the largest of the British Isles?" may be interpreted as "What is the largest island in the British Isles", and in that case, the answer would not be what you typed as the answer.
My apologies for these errors.