An act of sexual intercourse with a female complainant under any of the following circumstances: by forcible compulsion; by threat of forcible compulsion; the complainant was unconscious or unaware during intercourse; the alleged offender substantially impaired the complainant's power to appraise or control conduct by administering drugs, intoxicants or other means; the absence of consent; the complainant has a mental disability that renders her incapable of consent; or the victim is less than 13 years old.