You may cross examine any witness called by the prosecutor in the case in chief.
You need to study up on how to cross examine if you do decide to represent yourself.
It is complicated.
It will be difficult to beat a ticket clocked using a laser when the alleged speed is so high above the posted speed. You may want to focus on whether the officer followed procedure and whether there are any mistakes with the ticket or his recollection of the events.
Your chances of winning the trial will increase if you hire an attorney to represent you. The attorney will be familiar with court procedures and have trial techniques to increase your chances of winning.
The information provided does not constitute legal advice and is presented without any representation or warranty whatsoever, including as to the accuracy or completeness of the information. Always contact an attorney when seeking legal advice.