Indicate the correct test procedure and reasoning. A researcher wishes to determine whether listening to music affects students' performance on memory test. He randomly selects 50 students and has each student perform a memory test once while listening to music and once without listening to music in random order. The scores of memory tests were recorded.

Option B: Paired t-test, since there is a "with music" and "without music" score for each person.

Step-by-step explanation:

In this question, we have 50 students where each student performed memory test once listening to the music and once without listening to music.

Now, it's obvious that the same set of people are used twice, i.e. once listening to music and second time without listening to music.

We cannot use pooled t test because we don't know about the standard deviation and it is also not a z test because population standard deviation is unknown.

Thus, this will be a case of paired t test or dependent t test because samples in both tests are dependent or same.

So, from the image i attached, the only option that corresponds with my explanation to use paired t-test is option B

answer: 75°

step-by-step explanation:

∠esk is the supplement of ∠edk, so is 100°. ∠esd = 1/2·arc ed, so is 25°.

since ∠esk = ∠esd + ∠dsk

you have 100° = 25° + ∠dsk . .

fill in known values 75° = ∠dsk . . . . .

subtract 25°

step-by-step explanation: