Question: The smallest of Hawaii's eight main volcanic islands which is home to the rare flowering plant, Euphorbia skottsvergii, get's how many cm of rainfall on average annually?

Context paragraphs:
Euphorbia amygdaloides: Euphorbia amygdaloides (wood spurge) is a species of flowering plant in the family Euphorbiaceae, native to woodland locations in Europe, Turkey and the Caucasus.  It is a bushy evergreen perennial, growing to a height of 80 cm , with dark green slightly hairy leaves about 6 cm long.  The complex green-yellow inflorescence (cyathium), typical of "Euphorbia", appears in late spring and early summer.

Juan Fernández Islands: The Juan Fernández Islands (Spanish: "Archipiélago Juan Fernández" ) are a sparsely inhabited island group reliant on tourism and fishing in the South Pacific Ocean.  Situated 670 km off the coast of Chile, they are composed of three main volcanic islands: Robinson Crusoe, Alejandro Selkirk and Santa Clara.  They are considered part of Insular Chile.

Euphorbia eleanoriae: Euphorbia eleanoriae is a rare species of flowering plant in the euphorb family known by the common name Nā Pali sandmat.  It is endemic to Kauaʻ i, Hawaii.  Like other native Hawaiian euphorbs it is called ʻ akoko locally.  This plant was only discovered in 1992 and described to science in 1996 as "Chamaesyce eleanoriae".  At that time there were fewer than 500 plants known, all occurring in small populations scattered across the sheer cliffs along the Nā Pali Coast of Kauaʻ i. By 2001 the total population had already dropped; only three populations were found, for a total of fewer than 50 plants.  The plant was federally listed as an endangered species of the United States in 2010.

Trochocarpa clarkei: Trochocarpa clarkei, commonly known as lilac berry, is a rare flowering plant in the family Ericaceae.  It is endemic to sub-alpine areas of Victoria in Australia.  It is a shrub which grows to around 30 cm high.  The flowers are maroon with a greenish base.  The fruits, which appear in autumn, are about 8 mm in diameter.  These are eaten by small mammals and birds.  The species occurs in subalpine areas of the southern highlands, often in association with "Eucalyptus pauciflora".

Euphorbia palustris: Euphorbia palustris (marsh spurge or marsh euphorbia) is a species of flowering plant in the family Euphorbiaceae, native to marshland throughout much of mainland Europe and western Asia.  It is an herbaceous perennial growing to 90 cm tall and wide, with narrow leaves turning red and yellow in autumn, and persistent, bright acid yellow flower-heads (cyathia), 15 cm across, in spring.

Sidalcea oregana var. calva: Sidalcea oregana" var.  "calva, the Wenatchee Mountains checker-mallow, is a very rare flowering plant variety that occurs only in five locations in the Wenatchee Mountains of Chelan County, Washington, United States.  The plant has been placed on the Endangered species list.  It is the rarest known plant in Washington state.

Kahoolawe: Kahoʻ olawe ( ; Hawaiian: ] ) is the smallest of the eight main volcanic islands in the Hawaiian Islands.  Kahoʻ olawe is located about 7 mi southwest of Maui and also southeast of Lanai, and it is 11 mi long by 6.0 mi wide, with a total land area of 44.97 sqmi .  The highest point on Kahoʻ olawe is the crater of Lua Makika at the summit of Puʻ u Moaulanui, which is about 1477 ft above sea level.  Kahoʻ olawe is relatively dry (average annual rainfall is less than 65 cm ) because the island's low elevation fails to generate much orographic precipitation from the northeastern trade winds, and Kahoʻolawe is located in the rain shadow of eastern Maui's 10023 ft volcano, Haleakalā.  More than one quarter of Kahoʻ olawe has been eroded down to saprolitic hardpan soil.

Silene tomentosa: Silene tomentosa, the Gibraltar campion, is a very rare flowering plant of the genus "Silene" and the family Caryophyllaceae.  It is a woody-based perennial about 40cm high, with bilobed flowers ranging from pink to pale violet and is endemic to Gibraltar.

Hawaiian tropical dry forests: The Hawaiian tropical dry forests are a tropical dry broadleaf forest ecoregion in the Hawaiian Islands.  They cover an area of 6600 km2 on the leeward side of the main islands and the summits of Niʻ ihau and Kahoʻ olawe.  These forests are either seasonal or sclerophyllous.  Annual rainfall is less than 127 cm and may be as low as 25 cm ; the rainy season lasts from November to March.  Dominant tree species include koa ("Acacia koa"), koaiʻ a ("A. koaia"), ʻ akoko ("Euphorbia" spp.) , ʻ ōhiʻ a lehua ("Metrosideros polymorpha"), lonomea ("Sapindus oahuensis"), māmane ("Sophora chrysophylla"), loulu ("Pritchardia" spp.) , lama ("Diospyros sandwicensis"), olopua ("Nestegis sandwicensis"), wiliwili ("Erythrina sandwicensis"), and ʻ iliahi ("Santalum" spp.) .  Endemic plant species in the dry forests include hau heleʻ ula ("Kokia cookei"), uhiuhi ("Caesalpinia kavaiensis"), and "Gouania" spp.  The palila ("Loxioides bailleui"), a Hawaiian honeycreeper, is restricted to this type of habitat.

Euphorbia skottsbergii: Euphorbia skottsbergii (syn.  "Chamaesyce skottsbergii") is a rare species of flowering plant in the euphorb family known by the common names coastal sandmat and Skottsberg's broomspurge.  It is endemic to Hawaii, where it is found in coastal shrublands on Oʻ ahu, Molokaʻ i, Maui, and Kahoʻ olawe.  Like other Hawaiian euphorbs, this plant is known locally as ʻ akoko.

Supporting paragraphs: Euphorbia skottsbergii Kahoolawe
Answer: 65