curved line connecting 2 more notes different pitches
Tie (music) In music notation, a tie is a curved line connecting the heads of two notes of the same pitch and name, indicating that they are to be played as a single note with a duration equal to the sum of the individual notes' values. A tie is similar in appearance to a slur, however slurs join notes of different pitches which need to be played independently, but seamlessly.
Grading on a curve In education, marking on a curve (BE) or grading on a curve (AE) (also referred to as curved grading, bell curving, or using grading curves) is a method of assigning grades designed to yield a normal distribution (also called the Gaussian distribution) among the students in a class.[1] The term "curve" refers to the bell curve, the graphical representation of the probability density of the normal distribution, but this method does not necessarily use any specific frequency distribution.