A situation in which different things exist in equal, correct or good amounts.balance scales 天平
An instrument for weighing things, with a bar that is supported in the middle and has dishes hanging from each end.

bar chart / bar graph 条形图
A diagram that uses lines or narrow rectangles(= bars) of different heights (but equal widths) to show different amounts, so that they can be compared.
base 底面; 根
- The line or surface forming the part of a figure that is most nearly horizontal or on which it is supposed to stand.
- The number that is raised to various powers to generate the principal counting units of a number system. Thebase of the decimal system.
- The number raised to the logarithm of a designated number in order to produce that designated number; the number at which a chosen logarithmic scale has the value 1.
12345 = 1×105 + 2×104 + 3×103 + 4×102 + 5×100
391.47 = 3×103 + 9×102 + 1×100 + 4×10–1 + 7×10–2
benchmark angles 基准角
Angles such as 45°, 90°, 180°, 270° … , that can be used as references.
billion 十亿
One thousand million: 1 000 000 000, 109.
binary 二进制
Relating to a system of numerical notation to the base 2, in which each place of a number, expressed as 0 or 1, corresponds to a power of 2.
1002(100B)、 11010.112(11010.11B)
7 = 22 + 21 + 20
9 = 23 + 0 + 0 + 20