who was elsa? what was her advice to Albert `?

Dear Student,

Elsa was Albert Einstein's cousin from Berlin whose dad had a business there. 
She advised Albert to just repeat the lesson in the examination, as and how it was taught in the class. Just learning the lesson by heart would do the trick, according to her. And understanding it was not essential. But the problem was that Albert wasn't good at learning things by heart. 

Regards