Need to pass
consider u = {x|x is a negative real number}. which is an empty set?
a {x|x ∈ u and x has a negative cube root}
b {x|x ∈ u and x has a negative square root}
c{x|x ∈ u and x is equal to the product of a positive number and –1}
d {x|x ∈ u and x is equal to the sum of one negative and one positive number}

B={x|x ∈ U and x has a negative square root} is an empty set.

Step-by-step explanation:

let U={x|x is a negative real number}

A= {x|x ∈ U and x has a negative cube root}

It is not an empty set as it contains -1 ∈A such that

∈U . Hence A≠∅

B= {x|x ∈ U and x has a negative square root}

Let there exist some x∈U such that =negative square root of x

but x is a negative real number and its square root must be complex which does not belong to set of real numbers.

for example ,for x=-4∈U

∉set of real numbers.

C={x|x ∈ U and x is equal to the product of a positive number and –1}

C≠∅ as -8∈C such that 8×-1=-8.

D {x|x ∈ U and x is equal to the sum of one negative and one positive number}

D≠∅ as -1∉D such that -1=-5+4.

70

step-by-step explanation:

2*5=10

4*15=60

60+10=

70

it has changed from the width and the height.

step-by-step explanation: