A kangaroo has a maximum gravitational potential energy during one jump of 770 J When the kangaroo lands on the ground 14% of the maximum gravitational potential
energy is transferred to elastic potential energy in one tendon.
The tendon has an unstretched length of 35.0 cm
When the kangaroo lands on the ground the tendon stretches to a length of 42.0 cm
Calculate the spring constant of the tendon.

Identify the correct relation showing that the radius r of the orbit of a moon of a given planet can be determined from the radius r of the planet, the acceleration of gravity at the surface of the planet, and the time τ required by the moon to complete one full revolution about the planet. determine the acceleration of gravity at the surface of the planet jupiter knowing that r = 71 492 km and that t= 3.551 days and r= 670.9 × 10^3 km for its moon europa.