Roma drove 345km from mississauga to sudbury in 3.5 hrs. she drove part of the way at 110km/h and the rest of the way at 90km/h. how far did she drive at each speed?

Consider u = {x|x is a negative real number}which is an empty set? o {x|x eu and x has a negative cube root}o {x|x eu and x has a negative square root}{x|x eu and x is equal to the product of a positive number and -1}{x|x eu and x is equal to the sum of one negative and one positive number?