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:
D
Step-by-step explanation:
assuming a 6 sided die half of the die is above 3 so 1/2
Answer:
$17200
Step-by-step explanation:
$450 x 36 = $16200
$16200 + $1000 = $17200
Answer:
1/5 is the answer eeeeeeeeeeeeee
Https://www.khanacademy.org/math/arithmetic/fraction-arithmetic/arith-review-comparing-fractions/v/c...