Consider u = {x|x is a positive integer greater than 1}. which is an empty set? {x|x ∈ u andone-half is prime} {x|x ∈ u and 2x is prime} {x|x ∈ u andone-half can be written as a fraction} {x|x ∈ u and 2x can be written as a fraction}

Is the number 128.439 a rational number

Atourist boat is used for sightseeing in a nearby river. the boat travels 2.4 miles downstream and in the same amount of time, it travels 1.8 miles upstream. if the boat travels at an average speed of 21 miles per hour in the still water, find the current of the river.

Q= {1.7, 1.1, 1.4, 2.1, 2.3, s}. what is the absolute difference between the greatest and least possible values of the median of set q? express your answer as a decimal to the nearest hundredth.