Consider a cloudless day on which the sun shines down across the United States. If 2708 kJ of energy reaches a square meter ( m 2 ) of the United States in one hour, how much total solar energy reaches the entire United States per hour? The entire area of the United States is 9,158,960 km 2

You use the atomic number to find out how many protons and neutrons there are in the atom. you use the atomic mass to find out how many protons and electrons there are in the atom. 

Reaction involved in present system is :   c12h22o11 + h2o → 2 c6h12o6the reaction system is obeying following rate law:   rate = k[c12h22o11]thus, it is a first order reaction.now, for 1st order reactionrate constant (k) =  given: initial conc. = 3.0 g, final conc. = 2.7 g, t = 2.5 h∴rate constant (k) =  ∴ k = 0.04215 h-1now, for 1st order reaction, half life = 0.693/k = 0.693/0.04215 = 16.4 hthus correct answer is option b

A-rna has coded instructions for making proteins, and dna translates the code.

The fraction of an original sample of tritium that remains unchanged after 24.62 years is 1/4. if you need the percentage it is 25%