F region
That portion of the ionosphere existing between approximately 160 and 400 km above the surface of the Earth, consisting of layers of increased free-electron density caused by the ionizing effect of solar radiation. Note 1: The F region reflects normal-incident frequencies at or below the critical frequency (approximately 10 MHz) and partially absorbs waves of higher frequency. Note 2: The F1 layer exists from about 160 to 250 km above the surface of the Earth and only during daylight hours. Though fairly regular in its characteristics, it is not observable everywhere or on all days. The principal reflecting layer during the summer for paths of 2,000 to 3,500 km is the F1 layer. The F1 layer has approximately 5 ´ 105 e/cm3 (free electrons per cubic centimeter) at noontime and minimum sunspot activity, and increases to roughly 2 ´ 106 e/cm3 during maximum sunspot activity. The density falls off to below 104 e/cm3 at night. Note 3: The F1 layer merges into the F2 layer at night. Note 4: The F2 layer exists from about 250 to 400 km above the surface of the Earth. The F2 layer is the principal reflecting layer for HF communications during both day and night. The horizon-limited distance for one-hop F2 propagation is usually around 4,000 km. The F2 layer has about 106 e/cm3. However, variations are usually large, irregular, and particularly pronounced during magnetic storms.
The Urban Dictionary Tee
My wife bought this for me, my only thing about the shirt, is the big Vernon on the front. I think I would prefer it situated and smaller type as if overva pocket. Other than that I love it. Seems to be of good quality and easy wearability, but I have only tried it on, so am uncertain. Thank you for making my day
shirt made me cum
Dick Aww man I love this shirt for eating
people shat on my shirt that said shart and im mad they took a shit on it instead of a shart
Necero's shirt i can use this in almost every phrase. This shirt allows me to do some great stuff with my kids and grandkids! i'd love for anyone who says same to get this shirt!
Bad! Why is this T-shirt named shitty fucking??What a bad name it is!Recommend?Never!😡
The shirts are amazing! I will be ordering again. And recommend them to others 🙂
My UD shirts are my favorites. They fit well, last long, and are unique. I always have people reading my back.
Amazing This shirt is SOOOOO comfortable and I love the definition
BEST SHIRT OF ALL TIME THIS IS THE BEST SHIRT OF ALL TIME. LITERAL FUCKING HELL OF A PLACE HAS BECOME A PART OF MY EVERDAY VOCABULARY AND I RECOMMEND IT FOR ANYONE WHO IS FORCED TO SIT IN A PLACE THEY HATE FOR AN HOUR EVERDAY. GO BUY THE MUG, SHIRT, OR SWEATSHIRT NOW!
Awesome tshirt This tshirt is awesome but my name isn't actually Jayson but i bought it for his b-day
good is it very. i like shirt much,,,,, it contabfortable like it i do.
The Fucklix t shirt is perfect but I am still waiting for the xlarge I ordered. These are gifts and will be just what is needed. Hope I receive the xlarge soon then it's time to give them to the people I ordered them for. So glad I saw them . Thanks.
My wife loves it. Nice quality and so funny for the wearer. Thank you!
The shirt fit amazing, package was shipped rather fast! Thank you so much..
It is absolutely perfect and I love wearing it. Thank You.
Love the short mine says bih on it
this shit stays on during sex
Love it! Buyed it for my sister but I had to make it say her favorite anime 💀✨
LOVR THIS SHIRT OML SO CUTEEEEE😍😍😍
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Size Guide
Measurements may vary by up to 2" (5 cm). Pro tip: Measure one of your t-shirts at home and compare!
A - Length
Measure from the top of the collar to the bottom hem
B - Width
Measure across the chest from armpit to armpit
Size Chart
| Size | Length | Width |
|---|---|---|
| XS | 27" | 16½" |
| S | 28" | 18" |
| M | 29" | 20" |
| L | 30" | 22" |
| XL | 31" | 24" |
| 2XL | 32" | 26" |
| 3XL | 33" | 28" |
| Size | Length | Width |
|---|---|---|
| XS | 69 cm | 42 cm |
| S | 71 cm | 46 cm |
| M | 74 cm | 51 cm |
| L | 76 cm | 56 cm |
| XL | 79 cm | 61 cm |
| 2XL | 81 cm | 66 cm |
| 3XL | 84 cm | 71 cm |