If the Stanford-Binet IQ test is a normal curve with mean of 100 and standard deviation of 20what percent of the population has an IQ below 90?

Catherine saved some money and plans to add the same amount each week to her savings account. the table represents the number of weeks that she will save, x, and the total amount of money that she will have in her account, y. weeks, x dollars in account, y 4 74 6 86 9 104 11 116 which linear equation represents catherine’s situation?