9514 1404 393
Answer:
100°
Step-by-step explanation:
Arc BC is twice the measure of inscribed angle BEC, so is ...
arc BC = 2×50°
arc BC = 100°
Answer:
The middle one in the second section
Step-by-step explanation:
I have had this question before
Since we cannot be 100% sure which test Frank did better on, we need to find a way to make the comparison doable. This can be done by converting Frank's score to the
standard score (or also known as the z-score).
The z-score is calculated through the following formula:

where X is Frank's original score.
Converting Frank's scores to a standard score accounting for both the mean and standard deviation of the population who took the test will make the comparison possible.
We get the following z-scores after conversion:


If you read up more on the concept of z-score, you may know that this score just means the amount of standard deviations a data falls with respect to the mean. Comparing Frank's two scores, we can see that they are both below the mean. However, it can be seen that Frank's z-score for his chemistry test is lower than his z-score for his biology test.
This suggests that Frank scored relatively poorer in chemistry than he did in biology.
ANSWER: Frank did better in his biology test.