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Son pares de palabras que guardan la misma relación, excepto:

Los elementos _________ presentan baja electronegatividad y ceden electrones fácilmente.

Son antónimos las palabras que

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Las armas nucleares son las armas más peligrosas de la Tierra. Una sola puede destruir una ciudad entera, con la posibilidad de causar la muerte de millones de personas, y poner en peligro el medio natural y las vidas de las futuras generaciones debido a sus efectos catastróficos a largo plazo. Los peligros que comportan estas armas derivan de su propia existencia. A pesar de que las armas nucleares solo se han utilizado dos veces en la guerra en los bombardeos de Hiroshima y Nagasaki de 1945, hoy en día quedan en el mundo, según informes, unas 22.000 y se han llevado a cabo más de 2.000 ensayos nucleares hasta la fecha. El desarme es la mejor medida de protección contra tales peligros, aunque el logro de este objetivo ha sido un reto inmensamente difícil.
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Choose the correct answer for each question according to the information in the text. Each line is numbered to help you identify them quickly.

Sunflowers Make Bees Poop—a Lot. Here's Why That's Good
Paragraph	Text
[1]	Bumblebees and other pollinators face many threats, including pesticide exposure,
[2]	climate change, habitat loss due to agriculture and development, and pathogens
[3]	that ravage multiple species. But a recent finding may help lighten their load.
[4]	Previous studies have shown sunflower pollen can work like a medicine for
[5]	bumblebees afflicted by a parasite called Crithidia bombi, a single-celled organism
[6]	that takes up residence in the bee's gut [and harms their health]. But scientists couldn't
[7]	explain how sunflower pollen vanquished C. bombi—did it boost the bees' immune
[8]	function, or perhaps poison the parasite directly?
[9]	New research, published in the Journal of Insect Physiology, shows the answer is
[10]	deceptively simple. "Sunflower pollen makes bumblebees poo a whole lot," says lead
[11]	author Jonathan Giacomini, which flushes the parasite out.
[12]	Plant products like nectar and pollen are a treasure trove of potential insect medicines
[13]	that scientists are just beginning to understand, he adds. "There are natural things out
[14]	there that bees are interacting with that can be beneficial for them," Giacomini says.
[15]	And by making changes to the landscape, scientists hope we can help give bees a
[16]	fighting chance.
[17]	Plant power
[18]	If you happen upon a fuzzy, buzzing, flying creature in eastern North America, there's
[19]	a strong chance it's a common eastern bumblebee (Bombus impatiens). Yellow and
[20]	black striped with a rump covered in soft hairs, they're social insects that live in
[21]	colonies and love a good crevice—they build their homes in birdhouses, woodpiles,
[22]	abandoned burrows, and dense grasses.
[23]	[They] are important pollinators, both in the wild and in agriculture, where they're raised
[24]	and used to pollinate crops including tomatoes and pumpkins. Like other pollinators,
[25]	bumblebees face many threats, and C. bombi isn't even the biggest bumblebee
[26]	bugaboo. On its own, the parasite doesn't have much of an effect on a bumblebee's
[27]	health. But when food is scarce, C. bombi can shorten a bee's lifespan and even
[28]	reduce the number of young queens a colony can produce.
[29]	Lynn Adler is an evolutionary ecologist at the University of Massachusetts Amherst
[30]	who studies interactions between plants and insects. For years, she and longtime
[31]	collaborator Rebecca Irwin at North Carolina State University suspected pollinators
[32]	might be getting dosed by flowers since plants often invest chemically active
[33]	compounds into their nectar and pollen to help their genetic payload arrive at
[34]	its destination.
[35]	"Many plant defensive compounds can be medicinal at certain doses," Adler says. After
[36]	all, "most of our human medicines come from plants."
[37]	Giacomini discovered the effect of sunflower pollen as an undergraduate working in
[38]	Adler's lab in 2018. From [these] very first tests, sunflower pollen dramatically reduced
[39]	C. bombi parasite load in common eastern bumblebees, often clearing infection
[40]	completely. "We've been shocked at how consistent and effective sunflower pollen
[41]	has been," Adler says.
Elizabeth Anne Brown, National Geographic

Which of the following best describes the results of Jonathan Giacomini's research?

Señala un ejemplo de sustantivación de adjetivos.

Características de países en desarrollo.
I. Alta natalidad
II. Baja esperanza de vida
III. Baja alfabetización
IV. Alto PIB

Selecciona el modo en el que está escrito la siguiente oración: “Roberto estudiará en esa universidad”.

Identifique a uno de los autores representativos del materialismo histórico.

¿Qué ecuación describe el siguiente proceso químico?

Las sales de amonio pueden ser formadas a partir de reacciones de neutralización del hidróxido de amonio, el cual se forma al burbujear trihidruro de nitrógeno en agua bajo altas presiones y temperaturas.