<image>Read the following problem and then answer the questions.

The figure shows a "tower" made of small triangles of the same size. Observe carefully and fill in the blanks:

(1) The number of small triangles contained in each "tower" is related to the number of layers. Can you describe the relationship between the number of small triangles and the number of layers?
(2) Do you know how many small triangles are contained in a "tower" with 100 layers?
(3) Can you determine the number of layers in a "tower" that contains 64 small triangles?