Home ยป In the open ocean, tsunami can travel ________ miles per hour with periods up to_________ minutes Natural Disasters MCQs In the open ocean, tsunami can travel ________ miles per hour with periods up to_________ minutes January 29, 2022 9 Views Q. In the open ocean, tsunami can travel ________ miles per hour with periods up to_________ minutes. A. 50; 20 B. 50; 60 C. 485; 20 D. 485; 60 Answer: 485; 60