What does this below rebus puzzle mean?

Can you divide numbers from 1 to 9 (1 2 3 4 5 6 7 8 9) into two groups so that the sum of the numbers of each group is equal?

Note: 9 cannot be turned over to make it 6.

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

A research team went to a village somewhere between the jungles of Africa. Luckily for them, they reached the day when quite an interesting custom was to be performed. The custom was performed once a year as they confirmed and was performed in order to collect the taxes from every male of the region.

The taxes were to be paid in the form of grains. Everyone must pay pounds of grain equaling his respective age. This means a 20-year-old will have to pay 20 pounds of grain and a 30-year-old will pay 30 pounds of grain and so on.

The chief who collects the tax has 7 weights and a large 2-pan scale to weigh. But there is another custom that the chief can weigh only three of the seven weights.

Can you find out the weights of the seven weights? Also, what is the maximum age of the man that can be weighed for the payment of taxes?

In two decks of cards, what is the least amount of cards you must take to be *guaranteed* at least one four-of-a-kind?

using four eights (8) and a one (1) and one mathematical symbol , create the number 100

John left on a horse on Thursday , was gone for two days, and came back on Thursday after completing his work. How did that happen?

I speak without a mouth, and hear without ears. I have no-body, but I come alive with the wind. What am I?

Use the numbers 2, 3, 4 and 5 and the symbols + and = to make a true equation. Conditions: Each must be used exactly once and no other numbers or symbols can be used.

Can you find the six hidden animals in the picture below?