Figure (a) shows a spring P extends by 5 cm when it is hung with a 0.5 kg weight. Figure (b) shows four springs P are arranged in a system and it is
hung with a 1.0 kg load.

What is the total extension of the spring system?

A 5.0cm
B 10.0 cm
С 15.0 cm
D 20.0 cm
E 25.0 cm

Noted: the figure （a）and （b）on the picture above

Thanks for giving answer to me.​

when a device is used in a circuit in which the voltage is 81 v, the current flowing through the device is 3 a. what is the resistance of the device?

a. 27 ω

b. 40.5 a

c. 243 ω

d. 243 a

the correct answer is a. 27

we have been given a quadratic function and we need to restrict the domain such that it becomes a one to one function.

we know that vertex of this quadratic function occurs at (5,2).

further, we know that range of this function is .

if we restrict the domain of this function to either or , it will become one to one function.

let us know find its inverse.

upon interchanging x and y, we get:

let us now solve this function for y.

hence, the inverse function would be if we restrict the domain of original function to and the inverse function would be if we restrict the domain to .