From the function definition "function sum(first, second, third)", we can see that there are three value/parameters are passed in the function.Then variable "result" will be the sum all the three values. After that it will print the all three values in new line. Then the function will return one value which is the sum of all three that is value of "result".As there is only one value returned by the return statement in the function.
you can connect to the wifi on your device it will say you are connected but the wifi will not be connected to the internet so you will be able to do nothing on it without the modem