Which computer component can be described as a printed circuit that can be inserted into a system board to add additional functionality to a PC?

Which of the following contains host records for a domain?

a. DNS b. WINS c. Linux server d. UNIX Web clients

What will be the output of the following statement?

txtBox.Text = (1234.567).ToString("C") (A) $1234.567 (B) 1,234.57 (C) $1234.57 (D) $1,234.57