Number 4 is : a light hour is a measure of time in space used to calculate the length of time between one object to another and one light hour equals 1.079 × 109 kilometers or 1.079e+9
The correct answer would be cells
There are many other renewable sources to use such as hydro power, and wind power. All of these are renewable and safe to the environment. One reason solar power may not be used is because of it's cost.
Yo sup??
the 1st, 3rs and 4th statement are true because electromagnetic waves can travel large distances and electromagnetic waves are visible (only 400-700 nm wavelenght)
Hope this helps
(A) We can solve the problem by using Ohm's law, which states:

where
V is the potential difference across the electrical device
I is the current through the device
R is its resistance
For the heater coil in the problem, we know

and

, therefore we can rearrange Ohm's law to find the current through the device:

(B) The resistance of a conductive wire depends on three factors. In fact, it is given by:

where

is the resistivity of the material of the wire
L is the length of the wire
A is the cross-sectional area of the wire
Basically, we see that the longer the wire, the larger its resistance; and the larger the section of the wire, the smaller its resistance.