Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
The northern side of the borough includes the largest park in New York City—Pelham Bay Park, which includes Orchard Beach—and the fourth largest, Van Cortlandt Park, which is west of Woodlawn Cemetery and borders Yonkers. Also in the northern Bronx, Wave Hill, the former estate of George W. Perkins—known for a historic house, gardens, changing site-specific art installations and concerts—overlooks the New Jersey Palisades from a promontory on the Hudson in Riverdale. Nearer the borough's center, and along the Bronx River, is Bronx Park; its northern end houses the New York Botanical Gardens, which preserve the last patch of the original hemlock forest that once covered the entire county, and its southern end the Bronx Zoo, the largest urban zoological gardens in the United States. Just south of Van Cortlandt Park is the Jerome Park Reservoir, surrounded by 2 miles (3 km) of stone walls and bordering several small parks in the Bedford Park neighborhood; the reservoir was built in the 1890s on the site of the former Jerome Park Racetrack. Further south is Crotona Park, home to a 3.3-acre (1.3 ha) lake, 28 species of trees, and a large swimming pool. The land for these parks, and many others, was bought by New York City in 1888, while land was still open and inexpensive, in anticipation of future needs and future pressures for development.
When was the Jerome Park Reservoir built?
A: in the 1890s

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
In the last years of the nineteenth century, Planck was investigating the problem of black-body radiation first posed by Kirchhoff some forty years earlier. It is well known that hot objects glow, and that hotter objects glow brighter than cooler ones. The electromagnetic field obeys laws of motion similarly to a mass on a spring, and can come to thermal equilibrium with hot atoms. The hot object in equilibrium with light absorbs just as much light as it emits. If the object is black, meaning it absorbs all the light that hits it, then its thermal light emission is maximized.
What is required for the electromagnetic field to come to thermal differences?
A: unanswerable

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
As an example, Santiago de Compostela, the political capital city, has an average of 129 rainy days and 1,362 millimetres (53.6 in) per year (with just 17 rainy days in the three summer months) and 2,101 sunlight hours per year, with just 6 days with frosts per year. But the colder city of Lugo, to the east, has an average of 1,759 sunlight hours per year, 117 days with precipitations (> 1 mm) totalling 901.54 millimetres (35.5 in), and 40 days with frosts per year. The more mountainous parts of the provinces of Ourense and Lugo receive significant snowfall during the winter months. The sunniest city is Pontevedra with 2,223 sunny hours per year.
How many days with frosts?
A: 6

Q: What is a question about this article? If the question is unanswerable, say "unanswerable".
Communication is observed within the plant organism, i.e. within plant cells and between plant cells, between plants of the same or related species, and between plants and non-plant organisms, especially in the root zone. Plant roots communicate with rhizome bacteria, fungi, and insects within the soil. These interactions are governed by syntactic, pragmatic, and semantic rules,[citation needed] and are possible because of the decentralized "nervous system" of plants. The original meaning of the word "neuron" in Greek is "vegetable fiber" and recent research has shown that most of the microorganism plant communication processes are neuron-like. Plants also communicate via volatiles when exposed to herbivory attack behavior, thus warning neighboring plants. In parallel they produce other volatiles to attract parasites which attack these herbivores. In stress situations plants can overwrite the genomes they inherited from their parents and revert to that of their grand- or great-grandparents.[citation needed]
This centralized system makes plant interactions possible?
A:
unanswerable