Task 2: Using XHTML and JavaScript you have create a web page Implement the function Searchingstrings that allow to search a sub-string in a given string and display the: First occurrence, Last occurrence, First occurrence from a given index and Last occurrence from a given index. You can use the following String methods: string. IndexOf(searchvalue, start) return the position of the first occurrence of specified character(s) in a string. string.lastIndexOf(searchvalue, start) return the position of the last occurrence of specified character(s) in a string. You can use the following string to test your solution: var letters = "abcdefghijklmnopqrstuvwxyzabcdefghijklm";

In C# please

1c) Average sentence length We will create a function ( avg_sentence_len ) to calculate the average sentence length across a piece of text. This function should take text as an input parameter. Within this function: 1. sentences : Use the split() string method to split the input text at every '.'. This will split the text into a list of sentences. Store this in the variable sentences . To keep things simple, we will consider every "." as a sentence separator. (This decision could lead to misleading answers. For example, "Hello Dr. Jacob." is actually a single sentence, but our function will consider this 2 separate sentences). 2. words : Use the split() method to split the input text into a list of separate words, storing this in words . Again, to limit complexity, we will assume that all words are separated by a single space (" "). (So, while "I am going.to see you later" actually has 7 words, since there is no space after the ".", so we will assume the this to contain 6 separate…

•is Valid Phone Number(): ReturnsTrue if the provided phone number (represented as a string) is cor-rectly formatted, otherwiseFalse. To be considered correctly formatted, phone numbers must bewritten as###-###-####, where#is a digit between 0 and 9 .•validatePhoneBook(): A phone book is a list where each entry is a phone book record (represented asa dictionary; see below for more details). This function checks each phone book record in the phonebook for correctly formatted phone numbers.A phone book record is a dictionary which initially has two keys: the key"name"mapped to thecontact’s name (string) and the key"phone number"mapped to that contact’s phone number (alsoa string).validatePhoneBook()adds a new key"valid"to the record with the valueTrueif the phonenumber is formatted correctly, otherwiseFalse.   1. Write white-box and black-box tests for the function is ValidPhoneNumber(). You should do this with-out Python, either on paper, or in a simple document. Don’t worry about…

Python Programming

5. Charge Account Validation If you have downloaded the source code from the Computer Science Portal you will find a file named charge_accounts.txt in the Chapter 07 folder. This file has a list of a com- pany's valid charge account numbers. Each account number is a seven-digit number, such as 5658845. Programming Exercises 403 program Write a program that reads the contents of the file into a list. The program should then ask the user to enter a charge account number. The program should determine whether the number is valid by searching for it in the list. If the number is in the list, the should display a message indicating the number is valid. If the number is not in the list, the program should display a message indicating the number is invalid. (You can access the

In python please

Given code line, std::string un_address = "405 East 42nd Street, New York, NY, 10017"; Fill in the blanks: 17 std::stoi(un_address) returns std::stoi (un_address.substr( std::stoi (un_address.substr(un_address.find("1"))) J 20)) returns 42 returns