The concept of zero—less than one, nothing, nada—is deceptively complex. The first placeholder zero dates back to around 300 BCE, and the notion didn’t make its way to Western Europe until the 12th century. It takes children until preschool to wrap their brains around the concept. But scientists in Australia recently discovered a new animal capable of understanding zero: the honey bee. A 2018 study finds that insects can be taught the concept of nothing.
- Some species camouflage patterns may be ...., granting those species a higher chance of survival in a heterogeneous environment.
(1) plastic 
(2) subtle
(3) singular
(4) consistent
(5) imitable
Any population increase beyond a certain level (1) ... greater (2) ... vegetable foods; thus, the ability of a society to choose meat over cereals always arises, from (3) ... the numbers of people.
(1) (A) necessitates (B) caters to (C) eludes
(2) (D) gratification of (E) recourse to (F) cultivation
(3) (G) replenishing (H) concealing (I) limiting
Select TWO answer choices.
While normal floods resulting from usual monsoon rainfall are ... the growth of the crop, recently there has been an increase in the frequency of high-intensity floods that do not have such welcome effects.
(1) conducive to
(2) hindered by
(3) devastating for
(4) deleterious or
(5) essential for
(6) indispensable to
When Ross makes a paleontology joke on Friends, some viewers might find it funnier when the quip—whether good or bad—is accompanied by audible laughter. Sitcoms traditionally achieve this either by recording a live audience or utilizing a pre-recorded laugh track. And they're definitely on to something.
