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no butts in line by wollap no butts in line :iconwollap:wollap 59 8 a well oiled machine by wollap a well oiled machine :iconwollap:wollap 56 9 cozy by wollap cozy :iconwollap:wollap 43 5 yes by wollap yes :iconwollap:wollap 85 21 raridentity by wollap raridentity :iconwollap:wollap 131 40 copy pasta by wollap copy pasta :iconwollap:wollap 104 19 ur by wollap ur :iconwollap:wollap 82 36 castles by wollap castles :iconwollap:wollap 106 18 yolk by wollap yolk :iconwollap:wollap 57 11 the taste you can friendship by wollap the taste you can friendship :iconwollap:wollap 72 28 thanks by wollap thanks :iconwollap:wollap 95 9 so fetch by wollap so fetch :iconwollap:wollap 66 8 fashion cents by wollap fashion cents :iconwollap:wollap 133 26 spideys by wollap spideys :iconwollap:wollap 100 30 superheroatmeal by wollap superheroatmeal :iconwollap:wollap 67 18 shazam by wollap shazam :iconwollap:wollap 66 19

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Another M by Pertheseus Another M :iconpertheseus:Pertheseus 997 47 Pinkie EQG4 by iojknmiojknm Pinkie EQG4 :iconiojknmiojknm:iojknmiojknm 441 9 Present. by Marenlicious Present. :iconmarenlicious:Marenlicious 1,211 61 Monster Musume is Magic! by freedomthai Monster Musume is Magic! :iconfreedomthai:freedomthai 965 82 What a fashionable towel by SarmaTeppou What a fashionable towel :iconsarmateppou:SarmaTeppou 231 11 Trixie being a silly horse by SarmaTeppou Trixie being a silly horse :iconsarmateppou:SarmaTeppou 636 21 Comfy pony by SarmaTeppou Comfy pony :iconsarmateppou:SarmaTeppou 493 13 To Your Knees by StePandy To Your Knees :iconstepandy:StePandy 3,425 180 Who's A Silly Pony? S4 Ep13 and S6 Ep7 by thegreatrouge Who's A Silly Pony? S4 Ep13 and S6 Ep7 :iconthegreatrouge:thegreatrouge 462 78 Noxious Fleshborer by KoTnoneKoT Noxious Fleshborer :iconkotnonekot:KoTnoneKoT 186 4 The Legend of Zelda - redesign in Sci-Fi by madmagnus The Legend of Zelda - redesign in Sci-Fi :iconmadmagnus:madmagnus 51 9 Best Friends - Request for dcencia by wandrevieira1994 Best Friends - Request for dcencia :iconwandrevieira1994:wandrevieira1994 956 53 Everybody's New Dragon Waifu by Manual-Monaro Everybody's New Dragon Waifu :iconmanual-monaro:Manual-Monaro 202 17 In Need of Nuzzles mk2 by CaptainPudgeMuffin In Need of Nuzzles mk2 :iconcaptainpudgemuffin:CaptainPudgeMuffin 1,074 76 Princess of Laughter by Yutaila Princess of Laughter :iconyutaila:Yutaila 157 15 The Castle Isn't Open by SunBusting The Castle Isn't Open :iconsunbusting:SunBusting 798 28

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no butts in line

Modern tennis balls must conform to certain criteria for size, weight, deformation, and bounce criteria to be approved for regulation play. The International Tennis Federation(ITF) defines the official diameter as 6.54–6.86 cm (2.57–2.70 inches). Balls must have masses in the range 56.0–59.4 g (1.98–2.10 ounces). Yellow and white are the only colors approved by the ITF, and most balls produced are a fluorescent yellow known as "optic yellow", first introduced in 1972 following research demonstrating they were more visible on television.

Tennis balls are filled with air and are surfaced by a uniform felt-covered rubber compound. The felt delays flow separayion in the boundary layer which reduces aerodynamic drag and gives the ball better flight properties. Often the balls will have a number on them in addition to the brand name. This helps distinguish one set of balls from another of the same brand on an adjacent court.

Tennis balls begin to lose their bounce as soon as the tennis ball can is opened. They can be tested to determine their bounce. Modern regulation tennis balls are kept under pressure (approximately two atmospheres) until initially used; balls intended for use at high altitudes have a lower initial pressure, and inexpensive practice balls are made without internal pressurization. A ball is tested for bounce by dropping it from a height of 254 cm (100 inches) onto concrete ; a bounce between 135 and 147 cm (53 and 58 inches) is acceptable—if taking place at sea-level and 20 °C (68 °F) with relative humidity of 60%; high-altitude balls have different characteristics when tested at sea-level.

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:icondoctor-derpy:
Doctor-Derpy Featured By Owner Sep 2, 2016  Student Filmographer
Happy birthday! :D
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:iconnautiical:
nautiical Featured By Owner Sep 1, 2016  Hobbyist Digital Artist
hap birth
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Streled Featured By Owner Sep 1, 2016   Traditional Artist
Happy birthday.
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PickleEbony Featured By Owner Sep 1, 2016  Student Digital Artist
Happy Birthdayy Birthday cake  icon 
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Rose150 Featured By Owner Sep 1, 2016  Hobbyist Digital Artist
happy birthday!
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HurricanestarPegasus Featured By Owner Sep 1, 2016   General Artist
Happy Birthday?
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HellArmy Featured By Owner Sep 1, 2016  Hobbyist General Artist
Merry Christmas! Santa Clause 
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VanillaGhosties Featured By Owner Sep 1, 2016  Hobbyist Digital Artist
Hepy Burday!
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CuteToyBonnie Featured By Owner Sep 1, 2016
Happy Birthday !
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Mailinya Featured By Owner Sep 1, 2016  Hobbyist Digital Artist
Happy birthday! birthday cake 
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