Which of the following correctly describes a production isoquant?

an isoquant is a curve that shows the least-cost combinations of inputs that can produce a given level of output.
an isoquant is a curve that shows all possible levels of output that can be produced at various input price levels.
an isoquant is a curve that shows all possible combinations of inputs that can produce a given level of output.
an isoquant is a curve that shows all possible combinations of inputs that are used to produce various levels of output.
an isoquant is a curve that shows all possible levels of output that can be produced in the short-run using one variable input.

In year 1, the bennetts' 25-year-old daughter, jane, is a full-time student at an out-of-state university but she plans to return home after the school year ends. in previous years, jane has never worked and her parents have always been able to claim her as a dependent. in year 1, a kind neighbor offers to pay for all of jane's educational and living expenses. which of the following statements is most accurate regarding whether jane's parents would be allowed to claim an exemption for jane in year 1 assuming the neighbor pays for all of jane's support? a. no, jane must include her neighbor's gift as income and thus fails the gross income test for a qualifying relative. b.yes, because she is a full-time student and does not provide more than half of her own support, jane is considered her parent's qualifying child. c.no, jane is too old to be considered a qualifying child and fails the support test of a qualifying relative. d.yes, because she is a student, her absence is considered as "temporary." consequently she meets the residence test and is a considered a qualifying child of the bennetts.