The Worlds Largest Shark Caught Physics Scares Me - Force Question?

Physics scares me - force question? - the worlds largest shark caught

In 1967, a football team was in high school in California, before
kg named Bob, whose mass is 2.20 × 102nd Suppose, after he fell
Throw teammates Bob cavort in the air, but not starting
Him.When Bob touches the ground, the acceleration of the average increase to
When hitting 75.0 m / s is 2 (Note that this Acceleration one
of a magnitude far greater than the acceleration of free fall.) average
the force exerted by the Earth to Bob during the collision.

and also need help

The whale shark is the largest species of fish in the world. Its mass is
Size of 2.00 × 104 kg, the equivalent of three half-mass
full-grown elephant. Suppose that a crane lifts a network kg with a whale 2.00 × 104
Hai from the ground. The network is the constant acceleration of tranquility in a
2.5 s interval until the network reaches a speed of 1.0 m / s. Calculate
the degree of stress to the cable network.

Thank you. = / Too much confusion.