Answer the following question given this paragraph: Another simple machine that uses a wheel is the pulley. A pulley is a simple machine that consists of a rope and grooved wheel. The rope fits into the groove in the wheel, and pulling on the rope turns the wheel. Figure below shows two common uses of pulleys. Q: A pulley is a simple machine that consists of a grooved wheel and? Choices: - a battery - a wedge - a lever - a rope A:
a rope

Answer the following question given this paragraph: Bacteria called cyanobacteria are very important. They are bluish green in color (see Figure below ) because they contain chlorophyll. They make food through photosynthesis and release oxygen into the air. These bacteria were probably responsible for adding oxygen to the air on early Earth. This changed the planet's atmosphere. It also changed the direction of evolution. Ancient cyanobacteria also may have evolved into the chloroplasts of plant cells. Q: Cyanobacteria are bluish green in color because they contain what? Choices: - chloroplasts - microbial - carbonate - chlorophyll A:
chlorophyll

Answer the following question given this paragraph: The carbon monoxide molecule is correctly represented by a triple covalent bond between the carbon and oxygen atoms. One of the bonds is a coordinate covalent bond , a covalent bond in which one of the atoms contributes both of the electrons in the shared pair. Q: In what kind of bond does one atom contribute both of the electrons in the shared pair? Choices: - a valence bond - a metallic bond - an ionic bond - a covalent bond A:
a covalent bond

Answer the following question given this paragraph: The general trend in electronegativity is that the value increases from left to right across a row in the periodic table and decreases down a column. The most electronegative element is fluorine, which has a value of 4.0. As discussed in the lesson "Trends in the Periodic Table," electronegativity increases across a row as the number of protons in the nucleus increases and therefore has a stronger pull. Electronegativity decreases down a column due to an increased effect of electron shielding in larger atoms. Q: Generally speaking, electronegativity values ______ from left to right across a row in the periodic table and _______ down a column. Choices: - reverse, descend - move, fall - decrease, increase - increase, decrease A:
increase, decrease