Mail page is frozen
The screen on e.mail has frozen.
iPad (3rd gen) Wi-Fi + Cellular
Close the Mail app in the Task Bar and re-launch.
Double-click the Home button to reveal Task Bar. Hold Mail app down for a second or two until it wiggle; tap the minus sign to close app.
If it still doesn't work, try a reset.
Hold the Sleep and Home button down until you see the Apple logo.