$3.$ We want to build a decision tree and need to determine which attribute to split on$.$ Show through the use of information gain $($entropy$)$ if we should split on a$1$ or a$2.$ See dataset as follows Instance A$1$ A$2$ A$3$ Target Class

$1$ T T $1\mathrm{.}0+$

$2$ T T $6\mathrm{.}0+$

$3$ T F $5\mathrm{.}0-$

$4$ F F $4\mathrm{.}0+$

$5$ F T $7\mathrm{.}0-$

$6$ F T $3\mathrm{.}0-$

$7$ F F $8\mathrm{.}0-$

$8$ T F $7\mathrm{.}0+$

$9$ F T $5\mathrm{.}0-$