Student questions and answers

Questions students asked about AP® and SAT® topics on FiveStudy, with community and FiveStudy answers.

How careful do I need to be about labeling axes on the AD-AS graph? (AP Macroeconomics)
Why is an inscribed angle half the central angle? (Geometry)
Where is the deadweight loss triangle and why does it exist? (AP Microeconomics)
How do I tell if demand is elastic or inelastic without doing the full calculation? (AP Microeconomics)
Why does a firm produce where MR = MC instead of where profit looks highest on the table? (AP Microeconomics)
What exactly is crowding out and which graph shows it? (AP Macroeconomics)
When do I use the money market graph versus loanable funds? (AP Macroeconomics)
What's the difference between independent, dependent, and control variables? (Integrated Science Intermediate)
Why does a reaction go faster when you heat it up? (Integrated Science Intermediate)
What's the difference between mass and weight? (Integrated Science Intermediate)
What does "defense in depth" mean in practice? (AP Cybersecurity)
Why is a long passphrase stronger than a short password with symbols? (AP Cybersecurity)
What's the actual difference between hashing and encryption? (AP Cybersecurity)
How can I tell how many real solutions a quadratic has without solving it? (Algebra 2)
What does a negative or fractional exponent actually mean? (Algebra 2)
Why do I get extraneous solutions when solving radical equations? (Algebra 2)
When do I use == versus .equals() to compare Strings in Java? (AP Computer Science A)
Why does removing items from an ArrayList inside a for loop skip elements? (AP Computer Science A)
Why does my recursive search return null even though the value is in the tree? (AP Computer Science A)
What's the difference between an expression, an equation, and a function? (Algebra 1)
What does it mean when I solve an equation and get 0 = 5? (Algebra 1)
Why do I flip the inequality sign when I divide by a negative? (Algebra 1)
What's the real difference between similar and congruent? (Geometry)
Why isn't SSA enough to prove two triangles congruent? (Geometry)
Why can't I just work left to right instead of using order of operations? (Pre-Algebra)
How do I know whether a problem wants GCF or LCM? (Pre-Algebra)
Why is a negative times a negative a positive? (Pre-Algebra)
Is forgetting usually a storage problem or a retrieval problem? (AP Psychology)
What's the clearest way to tell classical from operant conditioning? (AP Psychology)
How do I explain why a correlational study can't prove causation? (AP Psychology)
How do I find the period of something like y = 3sin(2(x − π/4)) + 1? (AP Precalculus)
Why does my rational function have a hole instead of a vertical asymptote? (AP Precalculus)
How do I tell from a table whether a function is linear, exponential, or logarithmic? (AP Precalculus)
What's the difference between a compiler and an interpreter? (IGCSE Computer Science)
How do I convert between denary, binary, and hexadecimal? (IGCSE Computer Science)
What's the difference between RAM and ROM? (IGCSE Computer Science)
Why do lists start at index 1 in the AP pseudocode but 0 in the languages I use? (AP Computer Science Principles)
What's the real difference between lossy and lossless compression on the exam? (AP Computer Science Principles)
What actually counts as an "abstraction" in the Create Performance Task? (AP Computer Science Principles)
When am I actually allowed to use L'Hôpital's Rule? (AP Calculus AB)
Do I need to write + C on a definite integral? (AP Calculus AB)
How do I tell whether a problem needs the chain rule or the product rule? (AP Calculus AB)
What's the difference between the radius and the interval of convergence? (AP Calculus BC)
Why does my parametric arc length answer come out too big? (AP Calculus BC)
How do I pick which convergence test to use on a series? (AP Calculus BC)
How do I find and classify the critical points of this function? (AP Calculus AB)
What's the difference between independent, dependent, and control variables? (Integrated Science Advanced)
Why does a reaction go faster when you heat it up? (Integrated Science Advanced)
What's the difference between mass and weight? (Integrated Science Advanced)

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