Don't know them all, but...
1. What is the earliest possible date for Easter Sunday?
I think 22 March
2. 6th April has been Easter Sunday four times in the last century. It is also the first day of which year?
I have no idea.
3. What was the cause of a disastrous Easter weekend in 2001, which saw many businesses facing financial ruin?
4. Over the Easter weekend in 1960, 100,000 people gathered in Trafalgar Square in what was, at the time, described as the ‘largest demonstration London has seen this century.’ Who were the organisers of this rally?
Sorry!
5. Easter last year was on 16th April. This was also the birthday of which British female singer, who had hits with songs including ‘Wishin’ and Hopin’, ‘Anyone Who had a Heart’ and ‘Son of a Preacherman.’ Name her.
Dusty Springfield
6. The date of Easter Sunday changes each year. How is the date decided?
First Sunday after the 14th of April in the west...I think it is the next Sunday in the East.
7. Which Jewish festival is observed at roughly the same time of year as Easter?
Passover
8. The name, ‘Easter’ derives from an older Saxon festival, ‘Eastre’. Eastre was the pagan goddess of what?
Spring
9. What is Easter called in France?
10. What event is held every year in the grounds of the White House in Washington, DC, on Easter Monday?
I don't know. I would say an easter egg hunt.
11. In Australia, as well as eggs and bunnies, chocolate manufacturers also make chocolates in the shape of which native and endangered animal? The profits are then used to help protect these creatures.
Hmm...Koala Bear?
12. ‘Pancake Day’ is traditionally when all the indulgences in the kitchen were consumed prior to the Lenten season. Which festival, commonly celebrated on the same day, was originally designed as a more general way to ‘get it all out’ before the sacrifices of Lent?
Fat Tuesday!
13. ‘Angelino’ is a popular Easter dish from Italy. What is an ‘Angelino’ in this context?
Got me. Somthing to do with angels?
14. What is the difference between a hare and a rabbit?
Rabbits are born blind, and burrow. Hares don't. I think hares are faster too.
15. When are hot cross buns traditionally eaten?
Good Friday, or when the craving hits.