What is the value of this expression?

Which of the following answers is 5/25 simplified? 1/5 5/5 2/5 1/25

The standard deviation for a set of data is 5.5. the mean is 265. what is the margin of error?

40 points. given: two congruent angles ∠c and ∠r are supplementary. prove: ∠r and ∠c are both right angles. it doesn't have to be exactly 10 rows. statements reasons1. 1. 2. 2. 3. 3. 4. 4. 5. 5. 6. 6. 7. 7. 8. 8. 9. 9. 10. 10.