Salutations!
<span>You can see lightning before you can hear the thunder. Which is the best explanation for this?
The best explanation for this statement is the transmission of light in air is faster than the transmission of sound in the air. Light is faster than sound, thus you can see the thunder then you can hear the sound.
Hope I helped :D</span>
Answer:
Power, P = 722.96 watts
Explanation:
It is given that,
Voltage, V = 120 V
Length of nichrome wire, l = 8.9 m
Diameter of wire, d = 0.86 mm
Radius of wire, r = 0.43 mm = 0.00043 m
Resistivity of wire, 
We need to find the power drawn by this heater. Power is given by :

And, 


P = 722.96 watts
So, the power drawn by this heater element is 722.96 watts. Hence, this is the required solution.
The answer you have is right good job 12
The object's speed will not change.
In fact, after the astronaut throws the object, no additional forces will act on it (since the object is in free space). According to Newton's second law:

where the first term is the resultant of the forces acting on the body, m is the mass of the object and a its acceleration, we see that if no forces act on the object, then the acceleration is zero. Therefore, the acceleration of the object is zero, and its velocity remains constant.
Answer:
Vi = 5 m/s
Explanation:
let (a) acceleration = 0.75 m/s²
(t) time = 20 seconds
Vf = final velocity = 72 km/hr (convert to m/s to units consistency = 20 m/s)
find Initial velocity (Vi)
Vf - Vi
a = -----------
t
Vi = Vf - (a * t) = 20 - (0.75 * 20)
Vi = 5 m/s