What will be the best approach to finding all the prime numbers less than 75 that leave an odd reminder when we divide them with 5?

While house hunting in London, I came across a very good leasehold property Discussing the lease the landlady told me:

'The property was originally on a 99 years lease and two-thirds of the time passed is equal to four-fifths of the time to come. Now work it out for yourself and see how many years are to go!

What does below chemistry rebus means?

What is the fastest way to double your money?

What part of the chicken has the most feathers?

Can you find the missing letter in the sequence?
S - T - I - L - ? - T - F - Y - C

Find the next number in the series below

21 32 54 87 131 ?

The host of a game show, offers the guest a choice of three doors. Behind one is a expensive car, but behind the other two are goats.
After you have chosen one door, he reveals one of the other two doors behind which is a goat (he wouldn't reveal a car).

Now he gives you the chance to switch to the other unrevealed door or stay at your initial choice. You will then get what is behind that door.

You cannot hear the goats from behind the doors, or in any way know which door has the prize.

Should you stay, or switch, or doesn't it matter?

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

You walk into a room that contains a match, a kerosene lamp, a candle and a fireplace. What would you light first?