Mercator projection map <span />
I am going with x-rays; it is the most visible to the naked eye out of all the choices.
Dissecting microscopes used for the observation of larger objects and u can get a magnification of less than 100x.
<span>Dissecting microscopes are most often used by plant biologists
IM NOT VERY SURE</span>
If the medical assistant noted irregularities in the heart rate when palpating the radial pulse, they would opt to take a patients apical pulse for a full minute to make sure they are accurately counting the number of heartbeats per minute.