In a general Hilbert plane, opposite sides of a parallelogram need not be congruent, as is illustrated by Saccheri and Lambert quadrilaterals in non-semi-Euclidean planes. Prove that in a plane satisfying the Euclidean parallel postulate, opposite sides and opposite angles of a parallelogram are congruent.

Pleasse me i need an answer. give me the correct answer. answer if you know it ! the club will base its decision about whether to increase the budget for the indoor rock climbing facility on the analysis of its usage. the decision to increase the budget will depend on whether members are using the indoor facility at least two times a week. use the best measure of center for both data sets to determine whether the club should increase the budget. assume there are four weeks in a month. if you think the data is inconclusive, explain why.