(a) Within 30 days after service of the charge or notice of proposed adverse action, a respondent may file an answer. The answer shall include:

(1) A statement that the respondent admits, denies, or does not have and is unable to obtain sufficient information to admit or deny, each allegation made. A statement of lack of information shall have the effect of a denial. Any allegation that is not denied shall be deemed to be admitted.

(2) A statement of each affirmative defense and a statement of facts supporting each affirmative defense.

(b) Failure to file an answer within the 30-day period following service of the charge or notice of proposed adverse action shall be deemed an admission of all matters of fact recited therein and may result in the entry of a default decision.