Choose the correct variant1. one of many telephone lines connected to a central system in a large building, which all have different numbers Blank 1 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone 2. the sound you hear when you pick up the telephone that lets you know that you can make a call Blank 2 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone 3. the button on a telephone that has the symbol (#) on it Blank 3 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone 4. When you call somebody by mistake you say Blank 4 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone 5. When you want somebody to return your call you say Blank 5 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone 6. When you finish the telephone conversation you Blank 6 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone 7. When you ask somebody on the phone to wait until the person they want to talk to is available you say Blank 7 Hold on, please.hang up the phonepound keyI think I have the wrong number.Call me back, please.extensiondial tone