Atennis player throws a ball vertically upwards at 4.90 m/s. how long, in seconds, does the ball take to return to his hand (assuming it has not moved since releasing the ball)? assume a gravitational acceleration of g = 9.8 m/s^2 and give your answer to 2 decimal places.

Calculate the mass of an object that has a momentum of 100kg x m/sec and velocity of 4 m/sec

Athin nonconducting rod with a uniform distribution of positive charge q is bent into a circle of radius r. the central perpendicular axis through the ring is a z-axis, with the origin at the center of the ring. a) what is the magnitude of the electric field due to the rod at z = 0? n/c (b) what is the magnitude of the electric field due to the rod at z = infinity? n/c (c) in terms of r, at what positive value of z is that magnitude maximum? r (d) if r = 4.00 cm and q = 9.00 µc, what is the maximum magnitude? n/c

Give me a example of a decomposer. explain what would happen if decomposers were absent from a forest ecosystem