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New York's high rate of public transit use, over 200,000 daily cyclists as of 2014, and many pedestrian commuters make it the most energy-efficient major city in the United States. Walk and bicycle modes of travel account for 21% of all modes for trips in the city; nationally the rate for metro regions is about 8%. In both its 2011 and 2015 rankings, Walk Score named New York City the most walkable large city in the United States. Citibank sponsored the introduction of 10,000 public bicycles for the city's bike-share project in the summer of 2013. Research conducted by Quinnipiac University showed that a majority of New Yorkers support the initiative. New York City's numerical "in-season cycling indicator" of bicycling in the city hit an all-time high in 2013.

About what percentage of New York City travel is done by bike or on foot?
Answer: 21%
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Early web browsers supported only a very simple version of HTML. The rapid development of proprietary web browsers led to the development of non-standard dialects of HTML, leading to problems with interoperability. Modern web browsers support a combination of standards-based and de facto HTML and XHTML, which should be rendered in the same way by all browsers.

Modern browser support standards-based and defacto what?
Answer: HTML and XHTML
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Some bacteria produce intracellular nutrient storage granules for later use, such as glycogen, polyphosphate, sulfur or polyhydroxyalkanoates. Certain bacterial species, such as the photosynthetic Cyanobacteria, produce internal gas vesicles, which they use to regulate their buoyancy – allowing them to move up or down into water layers with different light intensities and nutrient levels. Intracellular membranes called chromatophores are also found in membranes of phototrophic bacteria. Used primarily for photosynthesis, they contain bacteriochlorophyll pigments and carotenoids. An early idea was that bacteria might contain membrane folds termed mesosomes, but these were later shown to be artifacts produced by the chemicals used to prepare the cells for electron microscopy. Inclusions are considered to be nonliving components of the cell that do not possess metabolic activity and are not bounded by membranes. The most common inclusions are glycogen, lipid droplets, crystals, and pigments. Volutin granules are cytoplasmic inclusions of complexed inorganic polyphosphate. These granules are called metachromatic granules due to their displaying the metachromatic effect; they appear red or blue when stained with the blue dyes methylene blue or toluidine blue. Gas vacuoles, which are freely permeable to gas, are membrane-bound vesicles present in some species of Cyanobacteria. They allow the bacteria to control their buoyancy. Microcompartments are widespread, membrane-bound organelles that are made of a protein shell that surrounds and encloses various enzymes. Carboxysomes are bacterial microcompartments that contain enzymes involved in carbon fixation. Magnetosomes are bacterial microcompartments, present in magnetotactic bacteria, that contain magnetic crystals.

What gas vacuoles are respoonsible for in bacteria?
Answer:
to control their buoyancy