Place an .ai File into Photoshop

Add an Illustrator file into an open Photoshop document by choosing File>Place while in Photoshop. You won't get any options for mode or resolution, as those are set by the existing document. The only factor you can control is the physical size of the placed Illustrator file. After placing and before the image is rasterized the image has handles that let you resize it. Press-and-hold the Shift key to keep your image proportionate as you make the image larger or smaller. When you're finished resizing, press Return (PC: Enter) and the object will be rasterized at that size.