I'm unable to adjust clip duration across multiple still image clips

I'm unable to identify how to adjust the clip duration across multiple clips.  In addition I was unable to identify how to set a default duration when importing multiple still images (something other than the default 2.5 seconds). I was simply wanting to do a quick slide show of photos, import and add music.  However importing 90-100 images and adjusting the image clip duration for each one separately is time prohibitive.  I can do this easier in MS PowerPoint.  What am I missing? [using Adobe Premiere Rush 1.5.12 (Build 554)]