Explain, why stringed musical instruments, like the guitar, are provided with a hollow box

Why are musical instruments provided with more than one string?

A stretched string is used in musical instruments because

Why we use air columns in musical instruments ?

Explain stringed and wind instruments. Describe how you can change the pitch in them.

Explain why strings of different thickness are provided on a stringed instrument.

The table below shows the results of a survey of 250 people who were asked whether they like to read and whether they play a musical instrument. According the the results, what is the probability that a randomly selected person who was surveyed likes to read, given that the person plays a musical instrument?

A sound is produced by plucking a string in a musical instrument, then

In a class of 40 students, 24 like to play guitar and 25 like to play piano. If each students like at least one of the musical instrutment, then how many like to play both piano and guitar?

Three musical instruments give out notes at the frequencies listed below. Flute : 400 Hz, Guitar : 200 Hz, Trumpet : 500 Hz. Which one of these has the highest pitch ?

The length of string of a musical instrument is 90 cm and has fundamental frequency of 120 Hz where should it be pressed to produce fundamental frequency of 180 Hz