Easements Revision! Just need a few pointers!

In 1970, Anne, the fee simple owner of Glebe Farm, agreed with her neighbour Belinda that Belinda might park her car from time to time in a garage on a corner of one of Anne’s fields near to Belinda’s house.

In 1978, Anne built a large greenhouse along the boundary of one of her fields and began to cultivate vegetables in it for sale. She put up a sign advertising fresh produce on the wall of the neighbouring building belonging to Charles.

Six months ago, Charles conveyed his property to Duncan, who has obtained planning permission to erect a building which will block out the light to Anne’s greenhouse. He has also objected to the presence of Anne’s sign on his building.

By 2006, Belinda had bought an electric car, and soon thereafter she discovered that the garage has electricity and so has now started plugging her car’s batteries into the mains to recharge. She has also acquired the freehold to the house on the other side of her original property for the purpose of letting, and has allowed her tenant Eddie to use Anne’s garage to park his car.

Advise Anne:
i) Whether she can maintain her sign on Duncan’s wall;
ii) Whether she can object to his planning permission; and
iii) whether she can prevent Belinda from parking her car on Anne’s land and using Anne’s electricity supply.