A closed pipe creates a fundamental frequency of 125 hz. What is the next higher frequency that will create a standing wave in the pipe? (speed of sound = 343 m/s) (Unit = Hz) 375 hz

With these questions , 15 pts & brainliest

Why does karst topography exist in some geographic location? a. few climates have enough oxygen b. most regions have rock layers other than limestone c. in most regions, the soil is too thin d. the water is too acidic enough in most places

What is the efficiency of an engine that does 80 j of work and exhausts 320 j of heat while taking in 400 j of heat ? a. 10% b. 20% c. 80% d. 25%