Suppose within your web browser you click on a link to obtain a web page. The IP address for the associated URL is already cached in your local host, so there is no DNS look$-$up$.$ Let RTT denotes the round trip time between the local host and the server containing the web page. Suppose the HTML file references four very small objects on the same server. Neglecting transmission time, how much time elapses with

$1.$ Non$-$ persistent HTTP with no parallel TCP connections?

$2.$ Persistent HTTP with no parallel TCP connections?

$3.$ Persistent HTTp with pipelining $($parallel connections$)$

$($answers in RTT plz$)$