Answer:
D) Both A and C are correct.
Step-by-step explanation:
If the sample contains 50 students, the percentage equivalent to each student is:

Each student corresponds to 2%, which means that percentages should be multiples of 2%.
21% is not a multiple of 2% and corresponds to:

21% of 50 students is 10.5 students, and you cannot sample a fraction of a student.
Therefore, Both A and C are correct.
Answer:
the answer is 1325
Step-by-step explanation:
Answer:
8x miles
Step-by-step explanation:
- runs with speed 8 mph
- bikes at an average speed of 14 mph
distance = speed * time
Here the speed for run is 8 mph and time is x hours
So distance covered: 8 * x = 8x miles.