A balloon expands and shrinks. Which type of cell does the balloon best model?
O A Bone cell because it is strong and stiff to provide support
OR Guard cell because it changes in size to open and close a hole
O Nerve cell because it sends electrical signals
Epithelial cell because it covers surfaces in a body

Ase your answer to this question on the information below.hydrocarbons and fissionable nuclei are among the sources used for the production of energy in the united states. a chemical reaction produces much less energy than a nuclear reaction per mole of reactant.the balanced chemical equation below represents the reaction of one molecule of a hydrocarbon with two molecules of oxygen.chemical equation: ch4 + 2o2 → co2 + 2h2o + 1.48 × 10−18 jthe nuclear equation below represents one of the many possible reactions for one fissionable nucleus. in this equation, x represents a missing product.nuclear equation: write an isotopic notation for the missing product represented by x in the nuclear equation.

Why is retrograde motion an apparent motion

Who determined the nature of chemical bonds?