Something that has become abundantly clear this year is that people love the challenge of a good old fashioned quiz. Whether it's a traditional pub quiz, or a virtual get together with friends and family from the comfort of our homes, many of us have been putting our general knowledge to the test. If you're keen to continue the learning, we've got you covered with a super speedy lesson on Botswana's Okavango Delta - a vast inland river delta in the north of the country - so that if the question "what is a delta?" comes up in your next quiz, you'll have all the answers.