Question $2[1$ pt$]$ Figure $2$ shows three neural network structures. $($a$)$ is a single layer neural

network, $($b$)$ is a one hidden layer neural network, and $($c$)$ is a two hidden layer neural network,

where each rectangle box denotes a one hidden layer network similar to $($b$).$

$$ Please draw decision regions for each network, respectively $[0\mathrm{.}5$ pt$],$

$$ Explain how the networks learn to classify samples into different categories $[0\mathrm{.}5$ pt$]$