Lena 2735 miles Mekong 4328 kilometers Click the icon to view a table of English and Metric Equivalents Select the correct choice below and if necessary fill in the answer box to complete your choice OA Mekong is the longer river by approximately km Round to the nearest whole number as needed B Lena is the longer river by approximately km Round to the nearest whole number as needed OC Both rivers are the same length rounded the nearest km English and Metric Equivalents English and Metric Equivalents 1 in 2 54 cm 1 ft 30 48 cm