It Is True . For A Function Each Input Should Only Have One OutPut .
Example ❤️ :
Input | Output
01 | 05
02. | 08
03. | 06
It Wouldn't Be A Function If The Input Had Repeated
Example ❤️ :
Input | Output
07. | 03
09. | 01
09. | 12
03. | 02
Well...what are the expressions and phrases???
sea level is 0 and a deck is above water, so 10 and below sea level is where people scuba dive, so the dot at -15