The y intercept is where it crosses the x axis. <span />
Answer:
a)
, b)
, c)
, d) 
Step-by-step explanation:
a) The spring constant is calculated by using this expression:



b) The work needed to compress the spring from its initial position is:

![\Delta U_{k} = \frac{1}{2}\cdot (300\,\frac{N}{m} )\cdot [(-0.3\,m)^{2}-(0\,m)^{2}]](https://tex.z-dn.net/?f=%5CDelta%20U_%7Bk%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ccdot%20%28300%5C%2C%5Cfrac%7BN%7D%7Bm%7D%20%29%5Ccdot%20%5B%28-0.3%5C%2Cm%29%5E%7B2%7D-%280%5C%2Cm%29%5E%7B2%7D%5D)

c) The work needed to stretch the spring is:
![\Delta U_{k} = \frac{1}{2}\cdot (300\,\frac{N}{m} )\cdot [(0.2\,m)^{2}-(0\,m)^{2}]](https://tex.z-dn.net/?f=%5CDelta%20U_%7Bk%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ccdot%20%28300%5C%2C%5Cfrac%7BN%7D%7Bm%7D%20%29%5Ccdot%20%5B%280.2%5C%2Cm%29%5E%7B2%7D-%280%5C%2Cm%29%5E%7B2%7D%5D)

d) The work need to stretch the spring is:
![\Delta U_{k} = \frac{1}{2}\cdot (300\,\frac{N}{m} )\cdot [(0.2\,m)^{2}-(0.1\,m)^{2}]](https://tex.z-dn.net/?f=%5CDelta%20U_%7Bk%7D%20%3D%20%5Cfrac%7B1%7D%7B2%7D%5Ccdot%20%28300%5C%2C%5Cfrac%7BN%7D%7Bm%7D%20%29%5Ccdot%20%5B%280.2%5C%2Cm%29%5E%7B2%7D-%280.1%5C%2Cm%29%5E%7B2%7D%5D)

Answer:
27 feet
Step-by-step explanation:
they go 27 feet because 15+6+6=27
Answer:
12.5
Step-by-step explanation:
It is equal to the slope of the line = 50/4 = 12.5
Answer:
C) The total revenue made selling candy bars.
Step-by-step explanation:
A dependent variable is one whose values depends on another variable. In y = 2x, the value of the variable y depends on x; therefore, y is the dependent variable. And since y is the total revenue made selling candy bars, the total revenue made selling candy bars is the dependent variable, which is choice C.
<em>Also, x is an independent variable, because its value does not dependent on anything—we are free to choose whichever value of x we like. </em>