1. 1/4 reason: if two children are A and B respectively, there are four situations: A male and B female, A female and B male, and the same male and female. The same male situation accounts for 1/4.

2. Reason A: If there are ***x movie tickets, A is about 1/2, B is about 3/x, C is about110, and D is about 1/x, which is obviously a high probability.

3. 1/2 Reason: It is similar to the question 1, but it is not determined which bus is the same as 28 or 54, accounting for 1/4+ 1/2.

4. No, because the number of balls in the bag is different (including red 1/2, yellow 3/ 10, white 1/5).

5.( 1) 6 kinds: A, B, C, B, C, B, C, B, C, B, B;

(2) Three types: A, B, C, B, C, A and B;

(3)1/2 (3 out of 6).

Expand the fifth power of (2x- 1) to 32x5-60x4+80x3-40x2+10x-1,

To make (2x-1) = ax5th power+bx4th power+cx3rd power+dx2nd power +ex+f hold, the corresponding coefficients are equal, so,

a=32

b=-60

c=80

d=-40

e= 10

f=- 1

ab +a -b+(b-a)b+(b-a)-b

= ab+a-b+b-a+b-a-b

= ab-a