they have zero momentum before pushing off, is at least true
Answer:
v = 54m/s
Explanation:

a = 7m/s²
u = 12m/s
t = 6s
7 = (v-12)/6
v - 12 = 42
v = 54m/s
(Correct me if i am wrong)
Answer:
The distance from the radio station is 0.28 light years away.
Solution:
As per the question:
Distance, d = 4 ly
Frequency of the radio station, f = 854 kHz = 
Power, P = 50 kW = 

Now,
From the relation:
P = nhf
where
n = no. of photons/second
h = Planck's constant
f = frequency
Now,

Area of the sphere, A = 
Now,
Suppose the distance from the radio station be 'r' from where the intensity of the photon is 



Now,
We know that:
1 ly = 
Thus

Answer:
C. turtles with genes for long necks had a better chance of surviving to reach reproductive age.
Explanation:
The turtles that had long necks were more fit to the environmnet in which they were lovated and were able to grow larger and have more reproductive time because of their ability to feed on grass and small shrubs, this helped them always haev food available, and made them the dominant gene eventually.
Answer: a. Mass per unit length =0.0245kg/m
b. Tension =2.45x10^-8N
C. Tension = 2.45 x10^-8N
Fundamental frequency =200Hz
Explanation: