5.2.3 Quiz: Parallelograms and Proofs Question 2 of 10
Which of the following are necessary when proving that the opposite sides of
a parallelogram are congruent? Check all that apply.
A. Opposite sides are perpendicular.
B. Opposite sides are parallel.
C. Corresponding parts of congruent triangles are congruent.
D. Corresponding parts of similar triangles are similar.

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?