One can simply say that the answer for the question 1+1= 2. However, how did we get to 2, is it because that is the way the world works? or is it the way how we been taught since we were kids? Math is an universal language, that is always been here and will be here long after humans have perished. Various sub categories of addition, subtraction, multiplication, and division in math is derived and proven by solving proofs, backing up your theories, showing the work and than let world be the judge of it. One can simply say 1+1=11, if he can prove his/her answer with enough data and logic. Math will evolve as people would try to break the barriers of the universe and it will eventually change into something that we might thing a rubbish idea today.
What is Marketing?
A question that has million different answers and each answer is both right and wrong at the same time. There will never be a true answer to this questions, because as the world progresses and the new ideas and inventions come through the market, each idea will face a specific trial and error and new ways must be invented to market that particular product, in-order to drive up the sells. Marketing is not just limited to selling or just physical items, it is infect an intangible thing that one can use it for both natural and unnatural things in the world. For as long as there is humans, there will always be a need for buying and selling, right and wrong, rich and poor, all of which can be sum up in one word "Marketing".
How one can master in basic chemistry by simply learning a periodic table?
Chemistry revolves around Periodic table, if one does not know anything about chemistry, he/she can still triumph in a subject by learning how the periodic table works. Look at the periodic table as a whole unit, than try to divide that unit in 4 parts, going from right to left, naming the unit whatever you prefer. The universal name for each part or a block is S,F,D,P blocks. Once you have achieved this, try to attack each block individually and master it by knowing what elements belong in which block and how they work with the adjacent blocks and elements. Once you have mastered your 4 blocks and mastered your atomic orbitals, you will have no trouble conquering the rest of chemistry, because everything revolves around orbital cycle.