I have branches, but no fruit, trunk or leaves. What am I?

What does this rebus riddle means ?

Christina, Allison and Lena are 3 daughters of John a well-known Mathematician, When I asked John the age of their daughters. He replied "The current age of her daughters is prime. Also, the difference between their ages is also prime."

How old are the daughters?

I am white when I am dirty, and black when I am clean. What am I?

A river should be crossed by a father, a mother and their two sons and two daughters.
There are some rules that should be followed while crossing the river. There can be only two people in the raft while crossing. The daughters cannot be with their father unless there is the presence of the mother. The sons cannot be with their mothers unless the father is present. Unless the guard is on the board, the criminals cannot be with any of the family members. Only the adults like the father, the guard, and the mother knows to use the raft.

How will they cross the river?

I am a five-letter word and comprises two different vowels and three same consonants. I am so strong that I can spoil your entire work.

Can you find out who am I?

Remove two matchsticks to make the below equation correct.

Can you think of a smallest +ve number such that if we shuffle the digits of the number, the new number becomes double the original number?

1. How can we put an elephant in the refrigerator?
2. How can we put a Giraffe in a refrigerator?
3. The king of the jungle invites all the animals to a party everyone comes except for one animal, which animal?
4. You come to a crocodile-infested lake, you can't go around it, you can't co under it and you can't go over it, how do you get across?

How do you go from 98 to 720 using just one letter?