Arcadia Entry Level Java Developer interview questions

Projects:- Explain projects --------------------------------------------- Java:- 1) Can you store different datatypes in an array? - No 2) What is the way to store different datatypes in an array? - Declare it as an object 3) What are the interfaces of collection? 4) Strings immutable - y? HTML; Radio / chech box - To enter only one option Puzzles 1) Arrange books in a library based on price - manually 2) Separate milk and water 3) 300 footballs black and white - arrange white after black -manually & code 4)5 litre can , 4 litre can - take water from stream and get 7 litres exactly using the two cans