2008 年

In the figure, $AB$ is the tangent to the circle at $B$ and $ADC$ is a straight line. If $AB:AD=2:1$, then the area of $\triangle ABD$ : the area of $\triangle BCD=$

Let $O$ be the origin. If the coordinates of the points $A$ and $B$ are $(48,0)$ and $(24,18)$ respectively, then the $y$-coordinate of the orthocentre of $\triangle ABO$ is

The equation of a circle is $x^2+y^2-4x-8y+11=0$. Which of the following are true? I. The coordinates of the centre of the circle are $(2,4)$. II. The radius of the circle is $3$. III. The origin lies outside the circle.

The bar chart below shows the numbers of cars sold for brand $A$, brand $B$ and brand $C$ in a certain month.

A sales representative makes the following claims: I. In that month, the number of cars sold for brand $C$ is two times that for brand $B$. II. In that month, the total number of cars sold for brand $A$ and brand $B$ is less than the number of cars sold for brand $C$. III. In that month, the number of cars sold for brand $A$ is $50\%$ less than that for brand $C$. Which of the above claims are false?