There are 27 formal amendments. Hope this helps.
The answer is Erosion, which is the the gradual destruction or diminution of something -- in this case, rocks. I hope this helps! For reference/perspective, sand is the product of rock erosion, because it's really just tiny remnants of crushed rock. Those "small pebbles" could be sand, but you'd have to emphasize just how small they are -- one grain of sand is just that: a grain
Checks and balances is the answer to this question.
The answer is D) They organized an airlift of supplies that lasted almost a year.
Hope this helps :)
