I am on the Trailhead = UX Prototyping Basics: Iterate on Your Prototype and I cannot get the Apex Controller, limit the account, contact and lead SOQL to return 5 records.  Can someone help me with what the code should be for this?

Can you please help me with what the correct code is to set the limiting query results to 5?

On the Salesforce Content Overview page, is there a way to get rid of the popular tags, recent activity and the Most active contributors page blocks. I wanted to know if I can avoid coding. 

I had already dropped this issue earlier, but didnt got the resolution.

While creating a new Opportunity, there are few vanilla fields i.e. "Close Date", "Probability" as static in system.
We can not make modifications in these fields.
"Probability": We don't need this field in system at all as it's not fitting as per business culture - It has to be removed.
"Close Date": It should not be mandatory, 
Although we had created a workflow which will automatically populate "Close Date" as system date depending on an another field "Stage".

While creating a new opportunity it should not be mandatory at all.

We are using "Professional Edition" with Workflows and APIs as Add-ons. 
Kindly let me know if this can be done if i can purchase anything?
I just need resolution here, as users are facing challenges and this effects our complete “Sales Pipeline”

I just added a new custom web tab with a simple url as http://www.google.com , after saving if I go that web tab it shows blank and no google page.

 

 

Kindly help as i am trying to do some serious work ( showing google.com is just a small thing but nfortunatly stuck here)

 

 

Thanks