Answer: The the speed of elevators is 22.55.
Explanation:
It is given that observation deck of the willis tower in Chicago Illinois is 1353 feet above the ground elevators lift visitors to that level in 60 seconds.
The speed is the change in distance with respect to time.

From the given information the total distance is 1353 and the total time is 60 seconds. So by the above formula we get,


Therefore, the speed of elevators is 22.55.
The square root of a a negative integer is imaginary.
It would still be a negative under a square root if you multiplied it by 2, therefor it will still be imaginary, or I’m assuming as your book calls it, undefined.
2•(sqrt-1) = 2sqrt-1
If you add a number to -1 itself, specifically 1 or greater it will become a positive number or 0 assuming you just add 1. In that case it would be defined.
-1 + 1 = 0
-1 + 2 = 1
If you add a number to the entire thing “sqrt-1” it will not be defined.
(sqrt-1) + 1 = 1+ (sqrt-1)
If you subtract a number it will still have a negative under a square root, meaning it would be undefined.
(sqrt-1) + 1 = 1 + (sqrt-1)
however if you subtract a negative number from -1 itself, you end up getting a positive number or zero. (Subtracting a negative number is adding because the negative signs cancel out).
-1 - -1 = 0
-1 - -2 = 1
If you squared it you would get -1, which is defined
sqrt-1 • sqrt-1 = -1
and if you cubed it, you would get a negative under a square root again, therefor it would be undefined.
sqrt-1 • sqrt-1 • sqrt-1 = -1 • sqrt-1 = -1(sqrt-1)
Sorry if this answer is confusing, I don’t have a scientific keyboard, I’ll get one soon.
You can download the app photo math and that will help you
The three numbers are 2, 5, and 11.
The sum of 3 numbers is 18. 2 + 5 + 11 = 18
Since the problem states that every number is a prime number, then the number must be a natural number greater than 1 that has no positive divisors other than 1 and itself.
2 / 1 = 2 OR 2 / 2 = 1 These numbers are prime numbers because their divisors
5 / 1 = 5 OR 5 / 5 = 1 are 1 and itself.
11/1 = 11 OR 11/11 = 1