Please help me in don't understand how to do this

Annabelle's homework is 75% it took her three hours how long should she estimate it will take her to complete her homework.

Ashley spent half of her lunch money on a turkey sandwich. then she spent two-thirds of the money she had left on a bottle of juice and the rest of the money on a cookie. if the cookie cost $.75, how much lunch money did ashley have to start with?

Asugar cube is inch on each edge. how much volume does it occupy?