I added individual steps for clarity. Note that g must be positive if the solution is to be real.

Let me know if you have any questions.
Answer:
Speed = 300 m/s
Explanation:
Given the following data;
Frequency = 150 Hz
Wavelength = 2 meters
To find the speed of the wave;
Mathematically, the speed of a wave is given by the formula:
Substituting into the formula, we have;
Speed = 300 m/s
Velocity means speed, while force means the strength or energy when doing something
Answer:
The puck moves a vertical height of 2.6 cm before stopping
Explanation:
As the puck is accelerated by the spring, the kinetic energy of the puck equals the elastic potential energy of the spring.
So, 1/2mv² = 1/2kx² where m = mass of puck = 39.2 g = 0.0392 g, v = velocity of puck, k = spring constant = 59 N/m and x = compression of spring = 1.3 cm = 0.013 cm.
Now, since the puck has an initial velocity, v before it slides up the inclined surface, its loss in kinetic energy equals its gain in potential energy before it stops. So
1/2mv² = mgh where h = vertical height puck moves and g = acceleration due to gravity = 9.8 m/s².
Substituting the kinetic energy of the puck for the potential energy of the spring, we have
1/2kx² = mgh
h = kx²/2mg
= 59 N/m × (0.013 m)²/(0.0392 kg × 9.8 m/s²)
= 0.009971 Nm/0.38416 N
= 0.0259 m
= 2.59 cm
≅ 2.6 cm
So the puck moves a vertical height of 2.6 cm before stopping
Answer:
Angular acceleration will be 
Explanation:
We have given that mass m = 0.18 kg
Radius r = 0.32 m
Initial angular velocity 
And final angular velocity 
Time is given as t = 8 sec
From equation of motion
We know that 


So angular acceleration will be 