Answer:
c. They hit at the same time
b. BGS
Explanation:
A marble dropped (initial vertical velocity is 0) will land at the same time as a marble launched horizontally (initial vertical velocity is 0) from the same height.
Boat S has a net speed of 5 m/s (10 − 5).
Boat B has a net speed of 15 m/s (10 + 5).
Boat G has a net speed of ≈11.2 m/s (√(10² + 5²)).
D) decreasing the temperature lowers the average kinetic energy of the reactants.
To solve this problem it is necessary to apply the equations related to the conservation of momentum.
This definition can be expressed as

Where
= Mass of each object
= Initial Velocity of each object
= Final velocity
Rearranging the equation to find the final velocity we have,

Our values are given as

Replacing we have,


Therefore the final velocity is 6.5m/s