7. How do your choices affect your personal carbon
footprint?

Elements and compounds are pure substances that cannot be broken down physically into a simpler substance. a physical change doesn’t break the bonds between atoms of a substance or form new ones. compounds can be broken down by a chemical change. a chemical change breaks chemical bonds and/or forms new ones between atoms of a substance. what simple substance would a compound break into? the basic elements that make it up! for example, if you passed a very strong electric current through water you’d break the chemical bonds in water and be left with oxygen and hydrogen. which of the following is an example of a chemical change? a separating water into different glasses b breaking frozen ice cubes with a hammer c running an electric current through water d boiling water to evaporate it on a stove

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

Label the steps for protein synthesis in order, beginning with the first steponce the protein is made, the gene for a particular trait is expressedmrna joins the ribosome, and the anticodons from trna join mrna to form a chain ofamino acidsrna polymerase unzips dna and free rna nucleotides join dna to form mrnav a chain of amino acids is formed from peptide bonds, creating a proteinmrna is transported from the nucleus of the cell to the ribosomes of the cell.