Undefined function 'symsum' for input arguments of type 'double'.

Which action is good business etiquette? a. switching your cell phone off before you enter a meeting b. keeping your cell phone on low volume before you enter a meeting c. setting a pleasant ring tone on your cell phone before you enter a meeting d. setting a standard ringtone on your cell phone before you enter a meeting

Linux is distributed under gnu gpl. why is this important? a. it ensures that only torvalds can profit from the sale of linux b. it prevents unknowledgeable users from downloading programs they don't know how to operate. c. it provides protection for the developers who created linux. d. it states that anyone can copy, modify, and share the program if changes are made public.

What are three software programs for mobile computing?