Let's solve each question step-by-step.
### Question 19
Which one of the following is NOT a valid reason for saving?
- A. For betting in football
- B. To maximize interest
- C. For vacation
- D. For the time of retirement
Answer:
A valid reason for saving is something that is typically considered responsible and legitimate financial behavior. Betting in football is generally not considered a responsible reason for saving because it involves a high level of risk and does not promote long-term financial stability. Therefore, the correct answer is:
- A. For betting in football
### Question 20
Which one of the following is true about the integral of a function f(x) with respect to a variable x?
- A. ∫f'(x)dx is the set of all anti-derivatives of f.
- B. ∫f(x)dx is the set of all anti-derivatives of f.
- C. ∫f'(x)dx is the set of all derivatives of f.
- D. ∫f(x)dx is the set of all derivatives of f.
Answer:
The integral of a function f(x) with respect to a variable x is defined as the set of all functions whose derivative is f(x). In other words, the integral of f(x), ∫f(x)dx, is the set of all anti-derivatives of f(x). Therefore, the correct answer is:
- B. ∫f(x)dx is the set of all anti-derivatives of f.
### Question 21
Which one of the following is a quantitative data?
- A. Measuring the heights of each student in the given class.
- B. Identifying the social status of individuals.
- C. Determining the tastes of foods in a restaurant.
- D. Checking the quality of a new product.
Answer:
Quantitative data is numerical and can be measured. Among the options, measuring the heights of each student in the given class is a quantitative measure, as heights are numerical values that can be measured and analyzed. Therefore, the correct answer is:
- A. Measuring the heights of each student in the given class.
### Question 22
What is the perimeter of a regular hexagon of radius 6cm?
- A. 18.3 cm
- B. 36 cm
- C. 18 cm
- D. 36.3 cm
Answer:
A regular hexagon can be divided into 6 equilateral triangles. The side length of each triangle is equal to the radius of the hexagon. Therefore, the perimeter of the hexagon is 6 times the radius.
Given the radius is 6 cm, the perimeter is:
[tex]\[ 6 \times 6 = 36 \, \text{cm} \][/tex]
The correct answer is:
- B. 36 cm
