Answer:
Option D
Step-by-step explanation:
Whenever we take a square root of a number the ± sign is with it like here in the question

And then x = ±4.47 which means x has two values one is +4.47 and the other is -4.47 so Option D is our answer.
Answer:
I think it 1oz
Step-by-step explanation:
No he did not because 20% of 250 is 50 and there are 90 students not 50 students!! Hope this helped you a lot !!!
Answer:
Option (2). 14 m
Step-by-step explanation:
Formula to get the area of a circle 'A' = 
where r = radius of the circle
Given in the question,
Area of the circle = 153.86 square meters
By putting the values in the formula,
153.86 = πr²
r = 
r = 
r = 7 meters
Diameter of circle = 2 × (radius of the circle)
= 2 × 7
= 14 meters
Therefore, diameter of the circle is 14 meters.
Option (2) is the answer.
Answer : B
the distance between the points (4,3) and (2,-1)
We apply distance formula

(x1,y1) is (4,3)
(x2,y2) is (2,1)


d^2 = 4+16 = 20
Take square root on both sides
So 
the distance between the points (4,3) and (2,-1) is 2sqrt(5)