Time.cs

public class Time
{
    private int seconds;

    private Time(int seconds)
    {
        this.seconds = seconds;
    }

    public static Time Hours(int n)
    {
        return new Time(n * 60 * 60);
    }

    public static Time Minutes(int n)
    {
        return new Time(n * 60);
    }

    public static Time Seconds(int n)
    {
        return new Time(n);
    }

    public int InMiliseconds()
    {
        return seconds * 1000;
    }

    public int InSeconds()
    {
        return seconds;
    }

    public int InMinutes()
    {
        return seconds / 60;
    }
}

[TestClass]
public class UnitTest1
{
    [TestMethod]
    public void Test()
    {
        Assert.IsTrue(Time.Hours(1).InMiliseconds() == Time.Minutes(60).InMiliseconds(), "1 hour should be the same as 60 minutes");
        Assert.IsTrue(Time.Minutes(60).InMiliseconds() == Time.Seconds(3600).InMiliseconds(), "60 minutes should be the same as 3600 seconds");
        Assert.IsTrue(Time.Seconds(60).InSeconds() == 60, "60 seconds should be 60 seconds");
        Assert.IsTrue(Time.Minutes(1).InSeconds() == 60, "1 minute should be 60 seconds");
        Assert.IsTrue(Time.Hours(1).InMiliseconds() == 3_600_000, "1 hour should be 3.600.000 miliseconds");
    }
}