Determine the total surface area of the leaves in cm 2 and record the value. Stepâ 2 Calculate the rate of transpiration/surface area. If you are using a gas pressure sensor to collect data, you can express these rate values as kPa/min/cm 2, where kPa (kilopascal) is a unit of pressure.Record the rate.etermine the total surface area of the leaves in cm 2 and record the value. Stepâ 2 Calculate the rate of transpiration/surface area. If you are using a gas pressure sensor to collect data, you can express these rate values as kPa/min/cm 2, where kPa (kilopascal) is a unit of pressure.
That's why cellphones are much more sophisticatedâand work in a completely different way. A cellphone handset contains a radio transmitter, for sending radio signals onward from the phone, and a radio receiver, for receiving incoming signals from other phones.
You can also turn off the Wi-Fi radio, too, just to be safe.  Avoid using your cell phone in places where you get a poor signal. Many consumers also don't realize that cell phones emit different amounts of radiation depending on where they are with respect to a wireless operator's cell phone tower.Use the speaker phone function of the cell phone. For the same reason you'd use a headset, using a speaker phone is another good option. It keeps the cell phone away from your body, and you don't have to worry about using a headset.