The only way to truly test if a variable is undefined is to do the following. Remember, undefined is an object in Javascript. To determine if a variable or object property exists, It is good to compare to keyword undefined or you can also check the type of the object to string âundefinedâ. In the following JavaScript code we compare the num to the undefined in both way.
Nuclear waste -- The waste from nuclear power plants will be toxic for humans for more than 100,000 years. Itâs untenable now to secure and store all of the waste from the plants that exist. To scale up to 2,500 or 3,000, let alone 17,000 plants is unthinkable.
4. High Cost: Another practical disadvantage of using nuclear energy is that it needs a lot of investment to set up a nuclear power station. It is not always possible by the developing countries to afford such a costly source of alternative energy.. High Cost: Another practical disadvantage of using nuclear energy is that it needs a lot of investment to set up a nuclear power station. It is not always possible by the developing countries to afford such a costly source of alternative energy.