Here is the code. I have attached the image of the error message:

using System; using System.Collections.Generic; using System.Linq; using NUnit.Framework; using OpenQA.Selenium; using OpenQA.Selenium.Firefox; using System.Text; using System.Threading.Tasks;

namespace BBC_W_FCast_New_01 { class Program { static void Main(string[] args) { //Instantiate Firefox Driver var driver = new FirefoxDriver(); driver.Navigate().GoToUrl("http://www.bbc.co.uk/weather");

        //Using the 'Find a Forecast' search field to get the weather in 'Reading, UK'
        var user = driver.FindElement(By.Id("locator-form-search"));

        //Use "Reading, Reading" to avoid ambiguity. There is a location called Reading in USA
        user.SendKeys("Reading, Reading");

        //Click on Search button
        driver.FindElement(By.Id("locator-form-submit")).Click();

        driver.Manage().Timeouts().ImplicitlyWait(TimeSpan.FromSeconds(10));

        //Click on Table button
        driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[10]")).Click();

        //Obtaining pressure For 2100 hours today
        driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[10]")).Click();
                                                 
        //Obtain pressure for 2100 Hours tomorrow
        driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[16]")).Click();

        //Subtract the two values above and then 'echo' the result in Selenium
        int val1 = Int32.Parse(driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[16]")).Text);
        int val2 = Int32.Parse(driver.FindElement(By.XPath(".//*[@id='hourly']/div[3]/table/tfoot/tr[3]/td[10]")).Text);

        int difference = val1 - val2;

System.Console.WriteLine("Difference is: " + difference);

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From my research, the answers I have found have the solution in Java & they do not offer good enough answers:

Selenium Webdriver: No such element exception even though element gets available after waiting for some time

http://stackoverflow.com/questions/20903231/how-to-wait-until-an-element-is-present-in-selenium

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I get an error message on adding this code:

//WebDriver Wait WebDriverWait wait = new WebDriverWait(driver, 30); wait.until(ExpectedConditions.visibilityOfElementLocated(By.id("locator")));

• Would appreciate your assistance. Thank you.