Điền số thích hợp vào ô trống: 241×123=

Trong cách đặt tính nhân một số với số có ba chữ số, tích riêng thứ ba lùi sang bên trái mấy hàng so với tích riêng thứ nhất?

A. 1 hàng

B. 2 hàng

C. 3 hàng

D. 4 hàng

Read the following passage and answer the questions below.

Everyone wants to reduce pollution. But the pollution problem is as complicated as it is serious. It is complicated because much pollution is caused by things that benefit people. For example, exhaust from automobile provides transportation to millions of people. Factories discharge much of the material that pollutes the air and water, but factories give employment to a large number of people.

Answer the questions.

Do you want to reduce pollution?

Loài cá thích nghi với đời sống tầng nước giữa:

A. Cá chép

B. Cá trích, cá nhám

C. Cá chép, cá trích

D. Cá nhám, cá đuối

Cho hàm số f x  đồng biến trên tập số thực ℝ , mệnh đề nào sau đây là đúng?

A. Với mọi x 1 , x 2 ∈ ℝ ⇒ f x 1 > f x 2 .

B. Với mọi x 1 , x 2 ∈ ℝ ⇒ f x 1 < f x 2 .

C. Với mọi x 1 > x 2 ∈ ℝ ⇒ f x 1 < f x 2 .

D. Với mọi  x 1 < x 2 ∈ ℝ ⇒ f x 1 < f x 2 .

Tổng nào sau đây có thể viết thành phép toán 13 x 3?

A. 13 + 13

B. 13 + 13 + 13 + 3

C. 13 + 3

D. 13 + 13 + 13

Read the passage and choose the best answer to the question.

AN EXCITING TRIP

I have just received a letter from my brother, Tim. He is in Australia. He has been there for six months. Tim is an engineer. He is working for a big firm and he has already visited a great number of different places in Australia. He has just bought an Australian car and has gone to Alice Springs, a small town in the center of Australia. He will soon visit Darwin. From there he will fly to Perth. My brother has never been abroad before, so he is finding this trip very exciting.

Whom was this passage written about?

A. Tim

B. Tim’s brother or sister

C. an engineer

D. Darwin