Define a Set $S$ Recursively as Follows:
I $\epsilon \in S$ II RECURSION: If

question 20

Essay

Define a set $S$ recursively as follows:
I. BASIS: $\epsilon \in S$
II. RECURSION: If $s$ and $t$ are in $S$ , then
$\begin{array} { l l l l } \text { a. } 0 s \in S & \text { b. } s 0 \in S & \text { c. } 1 s 1 t \in S & \text { d. } s 1 t 1 \in S \end{array}$
III. RESTRICTION: No strings other than those derived from I and II are in $S$ . Use structural induction to prove that every string in $S$ contains an even number of l's.

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Definitions:

Savanna

A grassland ecosystem characterized by the presence of scattered trees, maintaining an open canopy, found in tropical and subtropical regions.

Earth's Biomes

Large ecological areas on the planet's surface, defined by distinctive climate, soil, and vegetation types, such as deserts, forests, and tundra.

Altitude

The height of an object or point in relation to sea level or ground level.

Latitude

A geographic coordinate that specifies the north-south position of a point on the Earth's surface.