Dùng tam giác Pa-xcan, chứng tỏ rằng:  1   +   2   +   …   +   7   =   C 8 2

Có bao nhiêu cách sắp xếp chỗ ngồi cho mười người vào mười ghế kê thành một dãy?

cơ quan sinh dưỡng phát triển đa dạng

Fill in each numbered blank with one suitable word or phrase.

A thirteen-year-old does not spend as much money as his parents suspect - at least not (1) ………….the findings of recent survey, Money and Change. The survey (2) ……….. three hundred teenagers, 13-17 years old from (3) …………. Britain.

By the time they (4) ………… their teens, most children see their weekly allowance rise dramatically to an amazing national average of $5.14. Two thirds think they get (5) …………. money but most expect to have to do something to get it.

Although they have more cash, worry about debt is (6) ………….. among teenagers. Therefore, the majority of children make an effort to save for the future.

Greater access to cash (7) ……………. teenagers does not, however, mean that they are more irresponsible as a result. The economic recession seems to have encouraged cautious attitudes to money, even in the case of children at these ages. Instead of wasting what pocket (8) …………… they have on sweets or magazines, the teenagers who took (9) …………. in the survey seem to respond to the situation by saving more than half (10) …………. their cash.

Điền vào số 6

A. gaining

B. heightening

C. increasing

D. building

I accidentally ________ Mike when I was crossing a street downtown yesterday.

A. lost touch with

B. kept an eye on

C. paid attention to

D. caught sight of

\(-\left|\frac{9^2\cdot9^3}{3^{10}}\right|=-\left|\frac{9^5}{9^5}\right|=-1\)

0.5x-2/3x=7/6

1/2x-2/3x=7/6

x(1/2-2/3)=7/6

-1/6x=7/6

x=-7