2.A

3.D

4.( 1) 10 (2)0.5 (3)-9 (4)-3/2

5.( 1)-2 (2)3/4 (3) Original formula = 2/5+3/5 = 1

6. Solution: According to the meaning of the question, it is known that the side length of a small square is the cube root of 125/8, that is, 5/2 (cm).

The cube root of 7.2, the cube root of 2 n

8.-5

1.( 1) Because 0.1× 0.1× 0.1= 0.001.

So the cube root of 0.00 1 = 0. 1.

(2) Because 2× 2× 2 = 8

So the cube root of 8 = 2.

Because 4× 4× 4 = 64

So the cube root of 64 = 4.

(3). Because the cube of (-a) is equal to the cube of-a.

So-(-4) =-(-64) = the cube of 64.

So the square of the cube of -(-4) = the square root of 64 = 8.

Cube root of -(-4) = cube root of 64 = 4

(4) Let the first number be a, the second number be b and the third number be c,

Then the cube of a = A, ∴ A = 0, A = 1.

√b = b = ∴b≥0∴b's cube root b = 0, b = 1.

The cube root of √ c = c, ∴c≥0 and -√ c = c, ∴ c = 0.

There is obviously only one answer to this question, because

All real numbers have one and only one cubic root. (So the first question is wrong)

A positive number has a positive cube root, and the cube of a positive number is a negative number.

A negative number has a negative cube root, and the cube of a negative number is a negative number (so the second small question is correct).

Because 4× 4× 4 = 64, the cube root of 64 = 4 (that is, the third small question is wrong)

The square of any real number is non-negative (so the formula should be equal to 4, which is also wrong)

Write the rest another day.