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.
Nuclear power plants do not normally give off radiation that can be detected, but then can have accidental leaks of radioactive materials which, in turn give off radiation. Th â¦ ese can get into the environment and be dispersed, eventually causing damage.ince there is no  benefit from radiation, no amount of increase in exposure to  radiation is good. Nevertheless, there are things we cannot do  without exposure to radiation, such as getting dental X-rays or  consuming the amount of potassium we need every day.