Android is a software product developed by google that allows cell phone manufacturers to control hardware and establishes standards for developing and executing applications on its platform. android is thus an example of a(n)
a. operating system
b. programming language
c. user interface distributed system
d. database management system

Write a method public static string getdigits(string phonenumber) that takes an 11-character phone number written with any combination of 11 uppercase letters, lowercase letters and/or digits, and zero or more hyphens, and which returns the digits that a person would have to press on a cell phone to dial that phone number. we will use the mapping of letters to digits given at en.wikipedia.org/wiki/telephone_keypad# /media/file: telephone-keypad2.svg you may assume that the string parameter phonenumber contains some combination of exactly 11 uppercase letters, lowercase letters and/or digits, but that any number of hyphens may be present. you can assume that a hyphen will not appear as the first or last character of the string. do not assum