Solution:

52

sum of consecutive prime numbers
(2+3 , 5+7 , 11+13 , 17+19 , 23+29)

Solution:

11 / .11

Solution:

2(remember bodmas)

Solution:

charles put the ring into the box, secure it with one of your locks, and send the box to the girl firend.
She should then attach one of his own locks and return it. When you receive it again, remove your lock and send it back with her lock. Now she can unlock his own lock and retrieve the object.

Solution:

20 + 20 + 20

55 + 5

Solution:

Heroine

Solution:

Name

Solution:

2 people

Say 2 helpers are Helper1 & Helper2

Helper1 food Helper2 food McDuck's Food
End of Day 1 : 1 4 4
Now 'A' will head back

End of Day 2 : N/A 2 4
Now 'B' will head back

Now Mr. McDuck have 4 day food :-)

Solution:

The answer is C.

These are letter of the question asked in reverse order.

Solution:

0! or cos(0)