Dilation is when you stretch something by the same amount in two perpendicular directions. In other words, dilation changes size, not overall shape. If the factor of dilation is greater than one the shape is greater than the original, else if the scale factor is less than one the shape is smaller. In this problem, we must find the coordinates of A'. Since the center of dilation is the origins, we just need to multiply the coordinates of A by 0.5. So:
Helium, neon and Xeon belong to the same Column( Group) which is Column 18 or you can say Group 8 in roman numbers don't forget if you say group you should write in roman numbers okay. Best of luck