Please help answer correctly will mark brainliest

Question 13 of 451 pointwhich statement correctly describes the inverse of the following function? a. it is negative.b. it is a horizontal shift.c. it is not a function.d. it is a function. give an explanation as to why you chose that answer. (i think its either a or d.)

What is the result of adding the system of equations? 2x+y=4 3x-y=6

Scores on a university exam are normally distributed with a mean of 78 and a standard deviation of 8. the professor teaching the class declares that a score of 70 or higher is required for a grade of at least “c.” using the 68-95-99.7 rule, what percentage of students failed to earn a grade of at least “c”?