The rules that use the category "<answer>" are:

<degree_setting_in_tens-180>

<answer>

<digit-1> <digit-not_8_or_9> <answer>

<digit-not_0> <answer>

<degree_setting_in_tens-360>

<answer>

<digit-1_or_2> <digit> <answer>

<digit-3> <digit-not_6_or_7_or_8_or_9> <answer>

<digit-not_0> <answer>