1. The wrong one in the following statement is () The product of a number and zero is zero B a number is multiplied by 1, and the product is still this number The product of a number C with - 1 is the opposite of the number The product of a number multiplied by itself is a positive number 2. If a ● B = a ● B, there must be () A ab＞0 B ab≮0 C a＜0 b＜0 The symbols of D A and B are the same If two rational numbers are multiplied, (1) if one of the factors is replaced by its opposite number, (2) if two factors are replaced by their respective opposite numbers, what is the relationship between the product obtained and the original product? If M and N are rational numbers. And m ＜ n ＜ 0, then (M + n) × (m-n) 0 The rational numbers a, B and C are not zero. In the following cases, it is () A, B and C are the same number B a＞0，2b-3c=0 C a＜0，3b-2c=0 D a＜0，2b+3c=0 Answer today=

1. The wrong one in the following statement is () The product of a number and zero is zero B a number is multiplied by 1, and the product is still this number The product of a number C with - 1 is the opposite of the number The product of a number multiplied by itself is a positive number 2. If a ● B = a ● B, there must be () A ab＞0 B ab≮0 C a＜0 b＜0 The symbols of D A and B are the same If two rational numbers are multiplied, (1) if one of the factors is replaced by its opposite number, (2) if two factors are replaced by their respective opposite numbers, what is the relationship between the product obtained and the original product? If M and N are rational numbers. And m ＜ n ＜ 0, then (M + n) × (m-n) 0 The rational numbers a, B and C are not zero. In the following cases, it is () A, B and C are the same number B a＞0，2b-3c=0 C a＜0，3b-2c=0 D a＜0，2b+3c=0 Answer today=

1. The error in the following statement is that (d) a product of a number and zero is zero, B a product of a number and one is still this number, C a product of a number and - 1 is the opposite number of this number, d a product of a number and itself is a positive number. Note: the opposite number of C: 0 is also 0d: 0 * 0 = 0, not a positive number