The following network is a multi$-$layer perceptron, where all of the units have binary

inputs $(0$ or $1),$ unipolar step functions and binary outputs or $1).$

The weights for this network are $w_{31}=1,w_{32}=1,w_{41}=1,w_{42}=1,$ and $w_{43}=1.$ The

threshold of the hidden unit $(3)$ is $1\mathrm{.}5$ and the threshold of the output unit $(4)$ is $0\mathrm{.}5.$ The

threshold of both input units $(1)$ and $(2)$ is $0\mathrm{.}5,$ so the output of these units is exactly the same

as the input. Which Boolean functions can be computed by this network?