Answer:
Example of qualitative variable: hair colour.
Example of discrete quantitative variable: age.
a) Qualitative data displays are pie charts, histograms
b) Quantitative data displays are scatter and line graphs.
Step-by-step explanation:
A qualitative variable expresses a non-numerical quality of an object or person. For example, hair colour (brown, blonde, red...) or eye colour (green, blue, brown...).
A quantitative variable is a numerical value. For example, temperature (100 K, 2000 K...) or age (12 years, 20 years...).
A discrete quantitative variable can be obtained by counting, like the number of cars in a road. This is plotted in scatter graphs. For continuous variable, it can be obtained by measuring, like the height of your family members. This is plotted in line graphs.
- Pie charts: is a circular graphic that shows the statistics or number of people or objects with certain characteristics. For example, how many people have brown hair, how many are blonde and how many are redheaded.
- Histograms: they show vertical bars associated with the qualitative variable in the x-axis and the number of objects or people with that characteristic in the y-axis.
- Scatter: it is a graph with x and y axis and using Cartesian coordinates. Since it is for quatities, numbers can be represented as points.
- Line graphs: it is basically the same as a scatter plot but in this case the points can be joined by a line because the quantities are connected or are continuous.
Answer:
Angle OAB = 90°
Reason: tangent theorem of a circle
Step-by-step explanation:
The diagram given shows a tangent line of the given circle with center O. The tangent touches the circle at point A.
The diagram also shows the radius of the circle, OA, drawn from the center to the circle to meet at the point of tangency.
Thus, according to the Tangent Theorem of a circle, the point at which the radius drawn from the center meets the point of tangency = 90°. The tangent is perdendicular to the radius drawn to meet at the point of tangency.
Therefore, angle OAB = 90°
Answer:
Option C is correct.
Ratio of longer leg to hypotenuse is; 
Step-by-step explanation:
This is the special right angle triangle 30°-60°-90° as shown below in the figure.
- The side opposite the 30° angle is always the shortest because 30 degrees is the smallest angle.
- The side opposite the 60° angle will be the longer leg, because 60 degrees is the mid-sized degree angle in this triangle.
- Finally , the side opposite the 90° angle will always be the largest side(Hypotenuse) because 90 degrees is the largest angle.
In 30°−60°−90° right triangle,
- the length of the hypotenuse is twice the length of the shorter leg,also
- the length of the longer leg is
times the length of the shorter leg.
Then:
the sides are in proportion i.e, 
Therefore, the ratio of the length of the longer leg to the length of its hypotenuse is: 