The appearance of the final questions in the first volume of the fourth grade of mathematics: 1. Fill in the blanks 1.407000430 is a number (), and the highest digit is ((). 2. In the division formula, the divisor is 17, the quotient is 6, and the remainder is 6.

2. The number in the multiple-choice question 9.5□5090≈600000 □ is (). A.6 B.5 C.9 D.4 10。 △÷ 15

3. Answer the question 15. Write the number directly. 900 6 260 80 240 2 1