I have tried numerous times to complete this module - Automate Simple Business Processes with Process Builder with no success.  I've tried it in both my trailhead playground and my developers account.  I keep getting the following error message, even after deleting any process associated with contacts/accounts but still no luck.  Any suggestions would be helpful, thanks!

Challenge not yet complete... here's what's wrong:
There was an unexpected error in your org which is preventing this assessment check from completing: System.DmlException: Insert failed. First exception on row 0; first error: FIELD_CUSTOM_VALIDATION_EXCEPTION, Account Number must be 8 characters long.: []

I am having trouble understanding which environment I should work in (my developers environ or my trailhead playground) for the Control Access to Objects module under the Admin Intermediate Data Security trail.  I don't have any extra users I can activate in my dev license and I can't clone the profiles in the trailhead playground.  Please advise.  Thanks.

I have completed the challenge for the 'Use Static Resources' module and the preview shows the 'cat' image but the 'Check Challenge' function gives me the following message in a red box - "Challenge Not yet complete... here's what's wrong: 
The page does not include a reference to the specified image. HINT: The static resource does not require a '/' in the image URL. If you are using this, try removing and check again."

I've included the code I used to complete the challenge and it does include a reference to the specified image, otherwise how could it display.  Please advise.  Thanks.

<apex:page showHeader="false" sidebar="false" standardStylesheets="false">
    
        <!-- Display images directly referenced in a static resource -->
        <h3>Images</h3>
   
    <apex:image url="{!URLFOR($Resource.vfimagetest, '/cats/kitten1.jpg')}"/>          

</apex:page>

I am attempting to complete the Hands-On Challenge in the 'Use Standard List Controllers' module and the exercise doesn't reflect what I just learned in the module.  For example the apex:repeat command isn't explained so I have no real idea about how to use it.  Can someone please provide an explanation?  Thanks.

I can't get the Pagination piece of the course to work in my preview.  See the code I'm using per the instructions:

<apex:page standardController="Contact" recordSetVar="contacts">
  <apex:form>
    <apex:pageBlock title="Contacts List" id="contacts_list">
        
        Filter:
        <apex:selectList value="{! filterId }" size="1">
            <apex:selectOptions value="{! listViewOptions }"/>
            <apex:actionSupport event="onchange" reRender="contacts_list"/>   
        </apex:selectList>
        
        <!-- Contacts List -->
        <apex:pageblockTable value="{! contacts }" var="ct">
            <apex:column value="{! ct.FirstName }"/>
            <apex:column value="{! ct.LastName }"/>
            <apex:column value="{! ct.Email }"/>
            <apex:column value="{! ct.Account.Name }"/>
            
            <!-- Pagination -->
<table style="width: 100%"><tr>
    <td>
        Page: <apex:outputText 
    value=" {!PageNumber} of {! CEILING(ResultSize / PageSize) }"/>
    </td>            
    <td align="center">
<!-- Previous page -->
<!-- active -->
<apex:commandLink action="{! Previous }" value="« Previous"
     rendered="{! HasPrevious }"/>
<!-- inactive (no earlier pages) -->
<apex:outputText style="color: #ccc;" value="« Previous"
     rendered="{! NOT(HasPrevious) }"/>
&nbsp;&nbsp;  
<!-- Next page -->
<!-- active -->
<apex:commandLink action="{! Next }" value="Next »"
     rendered="{! HasNext }"/>
<!-- inactive (no more pages) -->
<apex:outputText style="color: #ccc;" value="Next »"
     rendered="{! NOT(HasNext) }"/>
    </td>
    
    <td align="right">
        Records per page:
<apex:selectList value="{! PageSize }" size="1">
    <apex:selectOption itemValue="5" itemLabel="5"/>
    <apex:selectOption itemValue="20" itemLabel="20"/>
    <apex:actionSupport event="onchange" reRender="contacts_list"/>
</apex:selectList>
    </td>
</tr></table>

            
            
            
        </apex:pageblockTable>
    </apex:pageBlock>
  </apex:form>
</apex:page>

I am having trouble understanding which environment I should work in (my developers environ or my trailhead playground) for the Control Access to Objects module under the Admin Intermediate Data Security trail.  I don't have any extra users I can activate in my dev license and I can't clone the profiles in the trailhead playground.  Please advise.  Thanks.

I have completed the challenge for the 'Use Static Resources' module and the preview shows the 'cat' image but the 'Check Challenge' function gives me the following message in a red box - "Challenge Not yet complete... here's what's wrong: 
The page does not include a reference to the specified image. HINT: The static resource does not require a '/' in the image URL. If you are using this, try removing and check again."

I've included the code I used to complete the challenge and it does include a reference to the specified image, otherwise how could it display.  Please advise.  Thanks.

<apex:page showHeader="false" sidebar="false" standardStylesheets="false">
    
        <!-- Display images directly referenced in a static resource -->
        <h3>Images</h3>
   
    <apex:image url="{!URLFOR($Resource.vfimagetest, '/cats/kitten1.jpg')}"/>          

</apex:page>

I can't get the Pagination piece of the course to work in my preview.  See the code I'm using per the instructions:

<apex:page standardController="Contact" recordSetVar="contacts">
  <apex:form>
    <apex:pageBlock title="Contacts List" id="contacts_list">
        
        Filter:
        <apex:selectList value="{! filterId }" size="1">
            <apex:selectOptions value="{! listViewOptions }"/>
            <apex:actionSupport event="onchange" reRender="contacts_list"/>   
        </apex:selectList>
        
        <!-- Contacts List -->
        <apex:pageblockTable value="{! contacts }" var="ct">
            <apex:column value="{! ct.FirstName }"/>
            <apex:column value="{! ct.LastName }"/>
            <apex:column value="{! ct.Email }"/>
            <apex:column value="{! ct.Account.Name }"/>
            
            <!-- Pagination -->
<table style="width: 100%"><tr>
    <td>
        Page: <apex:outputText 
    value=" {!PageNumber} of {! CEILING(ResultSize / PageSize) }"/>
    </td>            
    <td align="center">
<!-- Previous page -->
<!-- active -->
<apex:commandLink action="{! Previous }" value="« Previous"
     rendered="{! HasPrevious }"/>
<!-- inactive (no earlier pages) -->
<apex:outputText style="color: #ccc;" value="« Previous"
     rendered="{! NOT(HasPrevious) }"/>
&nbsp;&nbsp;  
<!-- Next page -->
<!-- active -->
<apex:commandLink action="{! Next }" value="Next »"
     rendered="{! HasNext }"/>
<!-- inactive (no more pages) -->
<apex:outputText style="color: #ccc;" value="Next »"
     rendered="{! NOT(HasNext) }"/>
    </td>
    
    <td align="right">
        Records per page:
<apex:selectList value="{! PageSize }" size="1">
    <apex:selectOption itemValue="5" itemLabel="5"/>
    <apex:selectOption itemValue="20" itemLabel="20"/>
    <apex:actionSupport event="onchange" reRender="contacts_list"/>
</apex:selectList>
    </td>
</tr></table>

            
            
            
        </apex:pageblockTable>
    </apex:pageBlock>
  </apex:form>
</apex:page>