Consider U = {x|x is a negative real number}. Which is an empty set? {x|x ∈ U and x has a negative cube root} {x|x ∈ U and x has a negative square root} {x|x ∈ U and x is equal to the product of a positive number and –1} {x|x ∈ U and x is equal to the sum of one negative and one positive number}

{x\ x e U and x has a negative square root} is an empty set.

Step-by-step explanation:

If x e U, x is a negative real number, and they don't have a square root (they don't have even roots). Their square roots are complex numbers, not real ones.

B

Step-by-step explanation:

e) none of the above because the measure of angle cba is 101°