<prompt> Which of the following statements is trueChronic myeloid leukemia occurs beyond 50 years of ageHairy cell leukemia in less than 50 years has a good prognosisAcute lymphoid leukemia in less than 1 year has a poor prognosisChronic lymphocytic leukemia occurs in less than 50 years of age  <response>: There are 4 main types of leukemia, based on whether they are acute or chronic, and myeloid or lymphocytic: Acute myeloid or myelogenous leukemiaAML Chronic myeloid or myelogenous leukemiaCML Acute lymphocytic or lymphoblastic leukemia ALL Chronic lymphocytic leukemia CLL 