Help me please, can u explain if you know, thanks

What is the value of the expression 9+n/3-6 when n = 12? 1. 5. 7. 12.

According to a study done by de anza students, the height for asian adult males is normally distributed with an average of 66 inches and a standard deviation of 2.5 inches. suppose one asian adult male is randomly chosen. let x = height of the individual. a) give the distribution of x. x ~ b) find the probability that the person is between 64 and 69 inches. write the probability statement. what is the probability?

Zahra wants the equation below to have an infinite number of solutions when the missing number is placed in the box.