If all Goats are Sheep and all Sheep are Deers, are all Deers Goats ?

Can you decipher these quotes by Albert Einstein?
Blf xzm mvevi hloev z kilyovn lm gsv ovevo lm dsrxs rg dzh xivzgvw.

Can you arrange four 9's and use at most 2 math symbols, to make the total 100?

What is the difference between a jeweller and a jailer?

He runs but never walks. Murmurs, but never talks. Has a bed, but never sleeps. And has a mouth, but never eats?

You are on your way to visit your Friend, who lives at the end of the hill. It is his birthday, and you want to give him the cakes you have made. Between your house and his house, you have to cross 5 bridges, and as it goes in the land of make believe, there is a troll under every bridge! Each troll, quite rightly, insists that you pay a troll toll. Before you can cross their bridge, you have to give them half of the cakes you are carrying, but as they are kind trolls, they each give you back a single cake. How many cakes do you have to leave home to make sure that you arrive at a friend's house with exactly two

Can you find out the number that should replace the question mark with a valid reason?

What mathematical symbol can be put between 5 and 9, to get a number bigger than 5 and smaller than 9?

What does the below rebus puzzle mean?

Three doctors said that Bill was their brother. Bill says he has no brothers. How many brothers does Bill actually have?