Evidence that Trump knew about Jr's meeting with the Russian lawyer:

[Kablooie]

Rob Goldstone in the Trump Jr. emails said:
"I can also send this info to your father via Rhona, but it is ultra sensitive so wanted to send to you first."

So it was definitely going to get to Trump sooner or later.

Then:
Tuesday Jun 7 - 5:20 PM - Trump Jr. scheduled the meeting for Thursday, June 9 at 3:00 PM to hear "information that would incriminate Hillary and her dealings with Russia"
Trump Jr. email

Tuesday June 7 - evening - Trump Sr. gave a speech and said:
"I am going to give a major speech on probably Monday of next week and we're going to be discussing all of the things that have taken place with the Clintons. I think you're going to find it very informative and very, very interesting. I wonder if the press will want to attend, who knows."
Trump speech transcript

So it's apparent that Trump knew about the scheduled meeting with the Kremlin lawyer.

[mobeau69]

1. Trump didn't know?

To borrow one from Ann Richards, That dog won't hunt.

[InAbLuEsTaTe]

2. As Sgt. Schultz would say... verrrrry innteresting!!

[GeoWilliam750]

5. Arte Johnson, perhaps?

[creeksneakers2]

3. If we can prove Trump knew about Russia's activities

Then Trump's denials that Russia was behind the hacks were a knowing cover up. That's collusion.

[C_U_L8R]

4. What did Rhonda know

And when did she know it?