Investigator williams arrives at a suspected crime scene, then sprays the area with a substance and turns off all the lights in an effort to find bloodstains invisible to normal eyes. what material, equipment, or technique is he using?

He is using luminol.

Explanation:

Luminol is a chemical substance that helps find bloodstains that are invisible to normal eyes. Luminol is a chemical substance that reacts to blood and other substances. The chemical reaction it has with blood it’s that it makes the substance more fluorescent. That is why is use in this type of scenes, because it makes it easier to locate and see all the possible bloodstains. Dry blood reacts better than fresh blood.

Luminol

Explanation:

I took the test, but also the notes say  "With this test, a luminol reagent is sprayed on surfaces or stains to see if blood is present.  If it is, the bloodstain will emit light or luminescence. "

1. cold turkey (no outside ). about 90% of people who try to quit smoking do it without outside support -- no aids, therapy, or medicine. although most people try to quit this way, it's not the most successful method. only about 5% to 7% are able to quit on their own.

2. behavioral therapy. this involves working with a counselor to find ways not to smoke. together, you'll find your triggers (such as emotions or situations that make you want to smoke) and make a plan to get through the cravings.

3. nicotine replacement therapy. there are several types, including nicotine gum, patches, inhalers, sprays, and lozenges. they work by giving you nicotine without the use of tobacco. you may be more likely to quit with nicotine replacement therapy, but it works best when you use it with behavioral therapy and lots of support from friends and family. and remember that the goal is to end your addiction to nicotine, not simply to quit using tobacco.

explanation:

mark brainliest