Answer:

Explanation:
Gravitational potential energy is the energy an object possesses due to its position. It is the product of mass, height, and acceleration due to gravity.

The object has a mass of 150 kilograms and is raised to a height of 20 meters. Since this is on Earth, the acceleration due to gravity is 9.8 meters per square second.
- m= 150 kg
- g= 9.8 m/s²
- h= 20 m
Substitute the values into the formula.

Multiply the three numbers and their units together.


Convert the units.
1 kilogram meter square per second squared (1 kg *m²/s²) is equal to 1 Joule (J). Our answer of 29,400 kg*m²/s² is equal to 29,400 Joules.

The crate has <u>29,400 Joules</u> of potential energy.
As we know that range of the projectile motion is given by

here we know that range will be same for two different angles
so here we can say the two angle must be complementary angles
so the two angles must be

so it is given that one of the projection angle is 75 degree
so other angle for same range must be 90 - 75 = 15 degree
so other projection angle must be 15 degree
1. D - sound travels the fastest through solids
2. 50 mm/s - v=fa
3. B - only process that involves changing waves




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I'm not really sure but I do know that it's not 0 because the object is still moving, even if it's only moving at 1 m/s.