/: susan makes $13 per hour. /: susan works over 30 hours per week. which of the following statements is equivalent to /? a. if susan works over 30 hours per week, then she makes $13 per hour. b. if susan makes $13 per hour, then she works over 30 hours per week. c. if susan makes $13 per hour, then she works over 30 hours per week, and if susan works over 30 hours per week, then she makes $13 per hour. d. if susan makes $13 per hour, then she works over 30 hours per week, or if susan works over 30 hours per week, then she makes $13 per hour.

Solve the given system of equations. 2y= -x+9 , 3x-6= -15

Ariana starts with 100 milligrams of a radioactive substance. the amount of the substance decreases by 20% each week for a number of weeks, w. the expression 100(1−0.2)w finds the amount of radioactive substance remaining after w weeks. which statement about this expression is true? a) it is the difference between the initial amount and the percent decrease. b) it is the difference between the initial amount and the decay factor after w weeks. c) it is the initial amount raised to the decay factor after w weeks. d) it is the product of the initial amount and the decay factor after w weeks.

Find the perimeter of the triangle with vertices  d(3, 4),  e(8, 7), and  f(5, 9). do not round before calculating the perimeter. after calculating the perimeter, round your answer to the nearest tenth.