We use the equation of motion for vertical component,

Here,
is displacement of bullet,
is vertical initial velocity of bullet which is equal to zero because bullet was fired horizontally, and t is time of flight.
Therefore,

Given, 
Substituting the values, we get time of flight

Answer:
The coefficient of static friction between the puppy and the floor is 0.7273.
Explanation:
The horizontal force applied to move the puppy from a steady state has to be greater than the force of static friction, after it is moving the force needs to be equal to be greater than the force of dynamic friction in order to maintain its movement. The force of static friction is given by:

Where
is the static friction force,
is the coefficient of static friction and
is the normal force. Since there's no angle on the flor the normal force is equal to the weight of the puppy, therefore,
, to make the puppy moving we need to use a force of 80 N, therefore,
, so we can solve for the coefficient as shown below:

The coefficient of static friction between the puppy and the floor is 0.7273.
Answer:
v = 8.45 m/s
Explanation:
given,
mass = 3 kg
angle = 30.0°
vertical distance = 3.3 m
μ = 0.06
according to conservation of energy
KE(loss) = PE(gain) + Work done (against\ friction)..............(1)
frictional Force


work against friction
W = F d


Potential energy
PE = mgh


v = 8.45 m/s
the minimum speed is equal to 8.45 m/s
v^2-u^2=2 x a x d
25^2-0^2=2 x a x 70
625-0=140 x a
625=140a
a=625/140
a=4.46 m/s^2
im not very sure but i think this is how you do this