"drag and drop" vs "place" image

[Hardrocker88]

I have a few questions, if any one can answer any of these it would be great.

So I am making a banner using Photoshop that will be 8ft wide by 4ft tall.
The company I am having this printed has this disclaimer about the the
images resolutions.

Resolution:
All file formats must have a minimum of 150 dpi (dot per inch) resolution at 100% of the final print size.
Print images need to be created at 350 dpi or there will be a substantial drop in the image quality.

- Does this mean that the actual banner file needs to be 350 dpi and any images I use in it need to be a minimum of 150 dpi?

- The next question has to do with my subject title. I am not sure which is better, to drag and drop an image or to place it. Which one actually places
the images at its actual size in relation to the file, in this case the banner file?
Because when I dragged and dopped it, the images was smaller compared to the same images placed in.

 

[smalltrees]

dpi... dots per inch, and ppi... pixels per inch, are both measurements, related somewhat... but, you cannot calculate between them...
seems like you are dealing with an old-school printer...

as far as your other question... your file will have one resolution...
if you add one file of a different resolution, to an existing file, you will see the differences on-screen... pixel dimensions need to match...
like putting a two inch square peg into a one inch hole...

 

[Hardrocker88]

Okay. Well, Im assuming that they want the file to be 350 resolution, because when I
downloaded one of their file templates, it was set to this size.

I guess my main concern is, which of the two processes are more accurate. As I have created a blank photoshop file sized at 72x36in, 350 resolution. I want to add an image to that file, a picture I took, which at its original state is 12x24in, 180 resolution. When I drag the picture in the size shrinks down, but when I place it, it retains its original size. Now because of the difference in resolution, I am wondering if the one that is dragged in is more accurate in size because of the resolution, or if I place it, even though it gets placed in at its original size (12x24in) the quality wont differ to much.