Gap junctions in the intercalated discs allow impulses to be spread across the heart more quickly. This is because gap junctions allow particles/signals to pass through, thus making cells with gap junctions more able to interact.
One more thing—you posted this in the physics section rather than biology.
The last one, handmade gifts require more of the givers time!
Answer : Total energy dissipated is 10 J
Explanation :
It is given that,
Time. t = 10 s
Resistance of the resistors, R = 4-ohm
Current, I = 0.5 A
Power used is given by :

Where
E is the energy dissipated.
So, E = P t.............(1)
Since, 
So equation (1) becomes :



So, the correct option is (3)
Hence, this is the required solution.
Uranus is much much larger than Earth, so the distance from the planet's center is much much greater
Answer:
Water falls from a reservoir through a channel to a turbine. The water turns the turbines, which allows the generator to make electricity.
It is falling instead of flowing, because elavation is an important part of the hydroeletric power plant, since gravity is a thing, and there was elevation, than it would be falling and not flowing.