If the charge at d is positive and the one at −d is negative but they are still equal in magnitude, in which direction does the electric field point at any point along the positive y − axis?.

Charlie is at an amusement park that has 18 different rides. each ride costs $1.75. the function c(r) = 1.75r represents the total amount of money that charlie will spend if he goes on r rides, but he never goes on the same one more than once. what domain and range are reasonable for the function?