Asquare matrix a is symmetric if a = ?

Wo audio speakers are placed on a vertical rail. speaker a is placed at head-level while speaker b is place at some variable height, \delta yδy, above speaker a. both speakers receive simultaneous input from a sine-wave generator so the speakers each produce a pure sinusoidal sound wave with a wavelength of 0.531 meters. calculate the lowest height that speaker b can be placed above speaker a to produce a minimum of sound heard by person standing \delta x = 7.86δx=7.86 meters directly in front of speaker a.

What are the examples for scaler quantities

Adistance-time graph indicates than an object moves 100 m in 4 s and then remains at rest for 6 s. what is the average speed of the object?