Change Default Duration Type. In the Duration column for the task type the duration in minutes m hours h days d weeks w or months mo. Sets the default date format to include a 4-digit year 2-digit month number and 2-digit day number.

Replace a transition effect. Select the tasks click the Tasks tab select the Information button in the Properties group click the advanced tab and make the change. Changing the Default Units.
Changing the Default Units.
Open properties set the duration to what you need Press the Default button Drag the picture from the preview window to the timeline or press to add it to the playlist first The photo duration is what you set the default to Drag another image in - the image duration is also the new default. I hope this helps. Fixed duration and units are the most common duration type for progressing the schedule. On the File tab click Options.