Rainfall and river height. The T-vector r gives the daily rainfall in some region over a
period of T days. The vector h gives the daily height of a river in the region (above its
normal height). By careful modeling of water flow, or by fitting a model to past data, it
is found that these vectors are (approximately) related by convolution: h = g ? r, where
g = (0.1, 0.4, 0.5, 0.2).
Give a short story in English (with no mathematical terms) to approximately describe
this relation. For example, you might mention how many days after a one day heavy
rainfall the river height is most affected. Or how many days it takes for the river height
to return to the normal height once the rain stops.