Answer:
Explanation:
A light year is a unit of length and is defined as "the distance a photon would travel in vacuum during a Julian year at the speed of light at an infinite distance from any gravitational field or magnetic field. "
In other words: It is the distance that the light travels in a year.
This unit is equivalent to
, which mathematically is expressed as:

Doing the conversion:
This is the distance from Earth to Sirius in miles.
Answer:
Weight is used most often for measuring solid whereas volume is used most often for measuring liquid.
Explanation:
Weight is used most often for measuring solid, because solids have definite shape. Weight is usually expressed in Newton (N) because it is a function of mass and gravity. ( weight = mass x gravity).
Whereas volume is used most often for measuring liquid, usually expressed in cubic meter (m³) because liquids have no definite shape, rather they occupy the volume of their container.

As per as my knowledge
The speed of a wave in a medium is affected by <u>d</u><u>e</u><u>n</u><u>s</u><u>i</u><u>t</u><u>y</u>,<u> </u><u>w</u><u>a</u><u>v</u><u>e</u><u>l</u><u>e</u><u>n</u><u>g</u><u>t</u><u>h</u> and <u>t</u><u>e</u><u>m</u><u>p</u><u>e</u><u>r</u><u>a</u><u>t</u><u>u</u><u>r</u><u>e</u><u> </u>:)
(Good luck on your test and mark me brainliest if this helps)
Answer:
Resistance of the iron rod, R = 0.000077 ohms
Explanation:
It is given that,
Area of iron rod, 
Length of the rod, L = 35 cm = 0.35 m
Resistivity of Iron, 
We need to find the resistance of the iron rod. It is given by :



So, the resistance of the rod is 0.000077 ohms. Hence, this is the required solution.