ChemistryGeneral Chemistry
Predicting Precipitation: ALEKS Answer
Only potassium sulfide with lead(II) nitrate forms a precipitate, PbS. The barium nitrate/acetate and iron(II) chloride/nickel(II) sulfate pairs remain soluble.
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MathAlgebra
ALEKS Vertical Line Test Answer: Does Graph 2 Represent a Function?
Graph 2 is not a function: the vertical line x = 0 crosses the diamond at two points, giving one input two outputs.
BiologyEvolution
Learning Through Art: Speciation Mastering Biology Answer
The seven placements connect morphological and biological species concepts to reproductive isolation, allopatric and sympatric speciation, hybrid zones, and reinforcement.
BiologyEvolution
Radiometric Dating Mastering Biology Answer: Carbon-14 Half-Life
A 12.5% remainder equals one-eighth of the starting carbon-14, or three half-lives, so the fossil's calculated age is 17,190 years.
ChemistryGeneral Chemistry
ALEKS Stoichiometry Answer: Empirical Formula from Percent Composition
A 100 g basis gives about 3.57 mol C and 3.58 mol O. Their smallest whole-number ratio is 1:1, so the empirical formula is CO.
BiologyGenetics
Mastering Biology Chapter 1 Answer Key: Why Is the Genetic Code Nearly Universal?
The shared genetic code is best explained by common ancestry. Its near-universality preserves a deep evolutionary signal while allowing for a small number of known exceptions.
MathTrigonometry
ALEKS Trigonometry Answers: Evaluate tan 47°, cos 38°, and sin 76°
In degree mode, the requested values round to tan 47° = 1.07, cos 38° = 0.79, and sin 76° = 0.97.
BiologyCell Biology
Mastering Biology Chapter 3 Answer Key: Which Statement Does Not Explain Water’s Hydrogen Bonds?
“Water is an electronegative molecule” is the exception. Oxygen is the electronegative atom; unequal O–H electron sharing makes the water molecule polar and enables hydrogen bonding.
StatisticsProbability
ALEKS Probability Answers: Two Independent Fisher Selections
The two selections are independent: 48/80 of Clearwater fishers have licenses and 45/90 of Mountain View fishers do not, giving an exact probability of 3/10.