Screenshot sizes for publishing android app on Google Play

Question

On the developer's console when you go to publish your android application the screenshots are needed with the following specifications, 320 x 480, 480 x 800, 480 x 854,1280 x 720, 1280 x 800 24 bit PNG or JPEG (no alpha) Full bleed, no border in art. Now on this link it says, "You may upload up to 8 screenshots." My questions is,

• What are the sizes for the last five screenshots? - The first three being - 320 x 480, 480 x 800, 480 x 854
• Is it 480 x 800 OR 480 x 854 for the second to eight screenshot or is it that second should be 480 x 800 and third should be 480 x 854 and fourth - eighth?
• Are the sizes 1280 x 720, 1280 x 800 only for tablets and are they optional?

Answer 1

• We require 2 screenshots.
• Use: Displayed on the details page for your application in Google Play.
• You may upload up to 8 screenshots each for phone, 7” tablet and 10” tablet.
• Specs: Minimum dimension: 320 pixels. Maximum dimension: 3840 pixels. The maximum dimension of your screenshot cannot be more than twice as long as the minimum dimension. You may use 24 bit PNG or JPEG image (no alpha). Full bleed, no border in art.
• We recommend adding screenshots of your app running on a 7" and 10" tablet. Go to ‘Store listing’ page in your Developer Console to add tablet apps screenshots.

https://support.google.com/googleplay/android-developer/answer/1078870?hl=en&ref_topic=2897459