Why, when studying "growth" and "decay", is Euler"s number "e" so pervasive?This activity aims to provide a clear understanding, and first-hand experience, that anything that grows "continuously" can be modelled (though it may not always be the "best" model) using this constant that, like π, seems to be one of the fixed "realities" of our physical universe.Some HL extension and "Exploration" ideas are offered in the...