A screen capture or screen shot is a photo of the entire phone screen. It is often used to show people maps, texts and other real-time information. You need only press it once, rather than holding it down. The outside border of the screen will also flash when the photo is taken. It will be saved in a screen shot folder alongside other types of photos. You can text or email the photo by sharing it from this folder.

Summary: Find the screen that you want to capture. Press and hold the Back button on the bottom right of your phone. Press the Home button simultaneously. Listen for a shutter sound indicating there was a screen capture. Access your screen shot in the Gallery app.

This instrument measures how much moisture is in the air or the relative humidity in an environment. It uses the cooling effect of evaporation to determine the relative humidity. Relative humidity is the ratio of water vapor in the air relative to the amount that could possibly be there, at a certain temperature. When you walk through fog, for example, you are experiencing 100% humidity. If you walk through a desert, you are experiencing around 10% humidity. To make your own sling psychrometer at home, you will need: Cotton gauze, in pads rather than balls A pair of scissors A small rubber band A liter empty plastic soda bottle Clear plastic tape 2 red alcohol Celsius thermometers Water An 18in (46cm) piece of string Use the water to moisten the gauze. This will help you capture moisture in your sling psychrometer. Cover 1 bulb of the thermometers with the wet gauze using a rubber band. Take the thermometer covered in gauze and place it on 1 side of the plastic bottle. Then, secure it there with tape. Take the other thermometer and attach it to the other side of the bottle using tape. Make sure you can still see the numbers and the red alcohol in the thermometers. Make sure the string is tied well on the the top of the bottle, as you will be holding it and spinning it to get a reading on your sling psychrometer. Hold tightly to the end of the string and spin the bottle in a circle in an open-air space. Do this for 1 minute. Then, record the temperatures on both thermometers. Record the 2 temperatures and then subtract the lower temperature from the higher temperature to determine the temperature difference. You will likely find that the thermometer with the wet gauze will always have a lower temperature than the thermometer with the dry bulb. The wet bulb temperature will always be lower than the dry bulb because water evaporates from the wet bulb when you spin the 2 thermometers. The evaporation then cools the wet bulb. The drier the air is, the more water will evaporate from the wet bulb, leading to a higher temperature difference between the wet and dry bulb. For example, you spin the sling psychrometer outside and the dry thermometer has a temperature of 22 degrees Celsius. You get a wet bulb temperature reading of 12 degrees Celsius. If the weather is very humid one day, you may get a dry bulb temperature of 22 degrees Celsius and a wet bulb temperature of 21 degrees Celsius. Because there is very little water evaporation on the wet bulb, this indicates that there is high humidity outside.

Summary: Be aware of the purpose of a sling psychrometer. Gather your supplies. Wet a double layer of cotton gauze. Attach the thermometers to the plastic bottle. Tie the string to the top of the bottle. Determine the difference between the 2 temperatures.

For the visual field test, it's important that you keep your eyes focused directly ahead. The doctor will stand about 3 feet (0.91m) in front of you. They will hold out their hand about 1 foot (0.30m) from one side of your face, and wiggle one of their fingers at the same level as your eyes. They'll ask you to confirm that you saw the finger wiggle. Testing your visual field involves making sure that your optic nerve correctly picks up and transmits visual data from your peripheral vision. It also determines if there are any lesions in your visual pathway. For a full visual field exam, the optometrist will test your optic nerve's ability to gather visual data in each of the four quadrants of your peripheral vision: upper-right, upper-left, lower-right, and lower-left. The doctor will repeat the finger-wiggling exercise three times, and ask you to confirm that you saw the movement of their finger. If at any point you cannot see motion in your peripheral vision, let the doctor know. This may indicate a problem with your optic nerve. This is a further means of testing your optic nerve's ability to pick up information in your peripheral vision. In a visual inattention test, the optometrist will hold out their hands as in a typical visual field exam, but they'll wiggle more than one finger simultaneously. The doctor will ask you to identify how many fingers they wiggled and which specific fingers they were.
Summary: Remain still and look straight ahead at the optometrist. Keep your eyes ahead while the doctor repeats the procedure. Ask the doctor about a visual inattention test.