This is a test of commonsense. Complete the next sentence:

How to reset a blackberry
Open the battery cover on the back of the blackberry.
Remove the battery from the phone.
You can perform a hard reset on the blackberry z10 by pressing and holding the power button on the top of the phone for about 10 seconds.
Reinsert the battery after a few seconds. To be on the safe side, wait for up to 30 seconds and then reinsert the battery into the back of the phone.