It's about one-fifty-five-thousandth as big as a Parking Space
In other words, the size of a Parking Space is 52,600 times 0.00000002850 hectares.(a.k.a Parking Stall) (average; surface lot; North America)
An average-size parking space in a North American surface lot measures 0.0015 hectares. Due to the high real estate prices at the time, parking spaces in a densely-populated part of Manhattan would sell for an average of $165,000 in 2007, with some spaces fetching up to $225,000.
It's about one-nine-hundred-thousandth as big as a Tennis court
In other words, 0.00000002850 hectares is 0.00000109249090 times the size of a Tennis court, and the size of a Tennis court is 915,339.430 times that amount.(per ITF specification; for doubles)
Per International Tennis Federation Rules of Tennis 2009, a doubles tennis court should measure 23.7744 m long by 10.9728 m, for a total area of about 0.026076 hectares. Courts may be surfaced with crushed red stone, shale, brick, hard-soil grass, or asphalt.
It's about 0.0000008 times as big as an IMAX screen
In other words, 0.00000002850 hectares is 0.00000080460 times the size of an IMAX screen, and the size of an IMAX screen is 1,243,000 times that amount.(standard)
An IMAX movie theater screen measures 22 m (72 ft) by 16 m (52 ft) for a total area of 0.03542 hectares. Because the film used in an IMAX movie is more than eight times larger than regular film, the platters of a two-and-a-half hour feature film can weigh up to 250 kg (550 lbs).
It's about 0.0000006 times as big as a Basketball court
In other words, 0.00000002850 hectares is 0.00000057501677020 times the size of a Basketball court, and the size of a Basketball court is 1,739,079.7140 times that amount.(per NBA regulation)
Per NBA rules , a basketball court should measure 29.5656 m long by 16.764 m wide, for a total area of 0.04956377184 hectares. The first basketball game, held in a Springfield Massachusetts YMCA, was played on a court half the size of today's NBA standard and ended with a score of 1-0.
It's about 0.0000003 times as big as Fort Knox
In other words, 0.00000002850 hectares is 0.0000002420 times the size of Fort Knox, and the size of Fort Knox is 4,130,000 times that amount.(a.k.a. the United States Bullion Depository, a.k.a. "Gold Vault") (Kentucky)
The United States Bullion Depository, commonly referred to by the metonym "Fort Knox" (in spite of the fact that the Depository is not located on the Fort proper), measures 32.0 m (105 ft) by 36.9 m (121 ft), for a total area of about 0.1180 hectares. The Depository is most famous for housing the largest portion of the national gold reserve, but has also temporarily housed the original US Declaration of Independence, an original copy of the US Constitution, and other important documents, kept there for safe keeping during World War II.
It's about 0.0000003 times as big as Manchester Cathedral
In other words, 0.00000002850 hectares is 0.00000023020 times the size of Manchester Cathedral, and the size of Manchester Cathedral is 4,344,000 times that amount.(a.k.a. Cathedral and Collegiate Church of St Mary, St Denys and St George) (Manchester, England, United Kingdom) (total interior area of Nave, Chapel, Library, Chapter House, and Rectory)
Manchester Cathedral includes a total interior area of 0.12380 hectares between the Nave, Chapel, Library, Chapter House, and Rectory. The height of the Cathedral's bell tower is 41.1 m.
It's about 0.0000002 times as big as a Hockey rink
In other words, 0.00000002850 hectares is 0.0000001878920090 times the size of a Hockey rink, and the size of a Hockey rink is 5,322,206.120 times that amount.(per NHL specification)
Per National Hockey League Official Rules, a hockey rink should measure 60.96 m long by 25.908 m wide with a corner arc radius of 8.5344 m, for a total area of about 0.1516828740 hectares. Ice hockey is believed to have developed from field hockey after players began holding games on ice rinks, which had been traditionally used for the sport of curling.