Frequency (f) = 500 hz (SI)
Velocity (V) = 1250 m/s (SI)
Wavelength (Lambda) = ? meters

Answer: The average velocity is 150 km/h
Explanation: 70+80=150
Answer: B
Explanation: look at the chart, easy
Answer: A hymn which accompanies religious observances and rituals. And others like guitar, violin, flute, harp and the organ
Explanation: Gradually people instructed the natives not only in singing but also in playing various instruments like guitar, violin, flute, harp and later on, the organ.