Ok heres what i know, one of the reasons why visible light will pass through glass but not through other materials is because the molecules in glass require more energy than average to push electrons from one level to another. Photons in visible light simply do not have enough energy. Only photons of light with shorter wavelengths, such as those that make up ultraviolet light, have the ability to change the electrons in glass. This is why ultraviolet light is unable to pass through glass. Lol im in 6th grade this is all i know ! :)
Answer : The time passed in years is 
Explanation :
Half-life = 5730 years
First we have to calculate the rate constant, we use the formula :
Now we have to calculate the time passed.
Expression for rate law for first order kinetics is given by:
where,
k = rate constant = 
t = time passed by the sample = ?
a = let initial amount of the reactant = X g
a - x = amount left after decay process = 
Now put all the given values in above equation, we get
Therefore, the time passed in years is
<span>1. A scientific hypothesis can become a theory if the hypothesis is tested extensively and competing hypothesis are eliminated. A scientific hypothesis is a proposed explanation made on the basis of reasoning without any assumption. For hypothesis to be termed a scientific hypothesis, it has to be something that can be supported or refuted through carefully crafted experimentation or observation.
2. A preliminary untested explanation that tries to explain how or why thing happen in the manner observed is a scientific hypothesis. A primary trait of a hypothesis is that something can be tested and that those tests can be replicated. A hypothesis is often examined by multiples scientists to ensure the integrity and veracity of the experiment. The process can take years, and in many cases hypothesis do not go any further in the scientific method as it is difficult to gather sufficient supporting evidence. </span>
A. good conductors is not a characteristic of metals out of all the other followings.
