Why do we obtain five missing values from the following lines of code?
150w, 300w" style="border-style:initial; border-width:0px; clear:both; display:block; font:inherit; height:auto; margin:18px auto; max-width:100%; padding:0px; transition:opacity 0.2s ease 0s; vertical-align:baseline; width:512px" class="aligncenter size-full tc-smart-loaded wp-image-71057">
NA is a logical type object and the logical vectors are reused to the equal length shared between vector and its subset. For example, x[NA] when iterated five times becomes x[NA, NA, NA, NA, NA].