Complete the story choosing the correct passive form of the verb

Complete the story choosing the correct passive form of the verb in brackets. It (to know) that in the past sweet dishes (to cool) with snow and ice. They (to enjoy) by the rich and powerful such as Alexander the Great, the Egyptian Pharaohs, and the Emperor Nero. The first real ice-cream (to make) with fresh cream and milk. It (to produce) in the 1630s by Gerald Tissain, the French chef of the British King, Charles I , During the 18th century ice-cream (to eat) regularly at 39; fashionable ice-cream cafes in London, Paris and other great cities. It was still a great luxury. For example, George Washington spent 200 on ice-cream for just two months in 1790. The cost (to reduce) when the first ice-cream factory (to build) in1851. At present the Italians (to know) as the great ice-cream makers. The Italian methods (to study) by many others, so today excellent ice-cream (to make) and (to enjoy) all over the world.