I say, and with God's help: She must perform ablution as long as she is able to do so, and she should only resort to dry ablution (tayammum) if she is unable to perform ablution. The method of tayammum is to strike the ground with both hands, then dust them off, and then wipe her face with them. After that, she strikes them again and wipes the back of one forearm and its inner side, including the elbow. And God knows best.