"lone parent" means, subject to regulations under section 162 - (a) a widow, (b) a widower, (c) a separated spouse, (d) an unmarried person, or (e) a person whose spouse has been committed in custody to a prison or place of detention for a period of not less than 6 months who has at least one qualified child normally residing with that person;
"allowance" means a lone parent's allowance;
"weekly means" means the yearly means divided by 52.
(2) For the purposes of this Chapter -
(a) means shall be calculated in accordance with the Rules contained in Part II of the Third Schedule, and
(b) a widow who has remarried shall not be regarded as the widow of her former husband and a widower who has remarried shall not be regarded as the widower of his former wife.