1. The problem statement, all variables and given/known data A curve of radius 68m is banked for a design speed of 85km/h. If the coefficient of static friction is 0.30 (wet pavement), at what range of speeds can a car safely make the curve? 2. Relevant equations 1) FNsin(theta) = m*v2/r 2) FNcos(theta) - mg = 0 3) tan(theta) = v2/rg 3. The attempt at a solution I used the third equation to find (theta) which is 39.9o but I can't find out how to find Ffr or the range of velocity I understand that when the car goes slow the frictional force faces up the banked curve and when it goes fast the friction goes down the banked curve but I can't figure out how to solve the question.