The general equation of the circle is expressed as (x-h)2 + (y-k)2 = r2 where (h,k) is the center of the circle. we are are given the center of the circle at (0,0) so the expression is simplified to <span>(x)2 + (y)2 = r2. given the other point, r2 is equal to 41. hence the final equation is x2 + y2 = 41</span>
<span>The Volume of a Cylinder = </span><span>π <span>• r² • height<span>
</span></span></span>radius = 13.5 feet
volume = PI * 13.5^2 * 4 feet (the problem states it is to be filled to a depth of 4 feet)
volume = PI * 182.25 * 4
volume =
<span>
<span>
<span>
2,290 cubic feet</span></span></span>
The hose delivers 80 <span>cubic feet per hour so it will take:
</span>2,290 / 80 =
<span>
<span>
<span>
28.625
</span>
</span>
</span>
hours
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The volume of the pool is:
volume = PI * 182.25 * 4.5
=
<span>
<span>
<span>
2,576.</span></span></span>5 cubic feet
Answer:The crystal structures of five 6-mercaptopurine derivatives, viz. 2-[(9-acetyl-9H-purin-6-yl)sulfanyl]-1-(3-methoxyphenyl)ethan-1-one (1), C16H14N4O3S, 2-[(9-acetyl-9H-purin-6-yl)sulfanyl]-1-(4-methoxyphenyl)ethan-1-one (2), C16H14N4O3S, 2-[(9-acetyl-9H-purin-6-yl)sulfanyl]-1-(4-chlorophenyl)ethan-1-one (3), C15H11ClN4O2S, 2-[(9-acetyl-9H-purin-6-yl)sulfanyl]-1-(4-bromophenyl)ethan-1-one (4), C15H11BrN4O2S, and 1-(3-methoxyphenyl)-2-[(9H-purin-6-yl)sulfanyl]ethan-1-one (5), C14H12N4O2S. Compounds (2), (3) and (4) are isomorphous and accordingly their molecular and supramolecular structures are similar. An analysis of the dihedral angles between the purine and exocyclic phenyl rings show that the molecules of (1) and (5) are essentially planar but that in the case of the three isomorphous compounds (2), (3) and (4), these rings are twisted by a dihedral angle of approximately 38°. With the exception of (1) all molecules are linked by weak C—H⋯O hydrogen bonds in their crystals. There is π–π stacking in all compounds. A Cambridge Structural Database search revealed the existence of 11 deposited compounds containing the 1-phenyl-2-sulfanylethanone scaffold; of these, only eight have a cyclic ring as substituent, the majority of these being heterocycles.
Keywords: crystal structure, mercaptopurines, supramolecular structure
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Chemical context
Purines, purine nucleosides and their analogs, are nitrogen-containing heterocycles ubiquitous in nature and present in biological systems like man, plants and marine organisms (Legraverend, 2008 ▸). These types of heterocycles take part of the core structure of guanine and adenine in nucleic acids (DNA and RNA) being involved in diverse in vivo catabolic and anabolic metabolic pathways.
6-Mercaptopurine is a water insoluble purine analogue, which attracted attention due to its antitumor and immunosuppressive properties. The drug is used, among others, in the treatment of rheumathologic disorders, cancer and prevent
Step-by-step explanation:
7.5 mph in 3 hours the train can travel 22.5 miles. Take 2.5 and times it by 3 to get the mph, then multiply that answer by 3 again to get the total miles in 3 hours
