Answer:
8 Joule
Step-by-step explanation:
Mass of block = 2 kg
Displacement = x = 800 mm = 0.8 m
Spring constant = k = 25 N/m
Potential Energy of a spring
Work done = Difference in Potential Energy
Work Done = Δ P.E.

⇒P.E. = 0.5×25×0.8²
⇒P.E. = 8 Nm = 8 Joule
Here already the spring constant and displacement is given so the mass will not be used while calculating the potential energy.
Answer:
y=1/3x-3
Step-by-step explanation:
use the eqation y-y1 = m(x-x1)
plug in slop as m and points as x and y
so now you have --> y-(-4)=1/3(x-(-3))
two negatives = a positive --> y+4=1/3(x+3)
distribute the 1/3 --> y+4= 1/3x + 1
subtract 4 from both sides --> y= 1/3x - 3
Answer: 
Step-by-step explanation:
Given : Number of choices for novels = 4
Number of choices for plays = 6
Number of choices for poetry books = 5
Number of choices for nonfiction books = 5
Total books =4+6+5+5=20
If he wants to include all 4 novels, then the number of books left to select = 9-4=5
Remaining choices for books = 20-4=16
Number of combinations of n things taking r at a time : 
Then, the number of different reading schedules are possible :_

Hence, the required answer is
.
Answer:
I think it can be 3 . Hope it help you