Basic General Knowledge
To produce sound it is necessary that

the source may execute any type of vibrations
the source should execute transverse vibrations
the vibrations of source are not necessary
the source should execute longitudinal vibrations

ANSWER DOWNLOAD EXAMIANS APP

Basic General Knowledge
Leonardo da Vinci

drew models of organs such as the heart, lungs and womb
was a great Italian painter, sculptor and architect
All of these
got universal fame form his masterpiece

ANSWER DOWNLOAD EXAMIANS APP