4. A 268 kg boulder rolls down a hill. If it had 50,000 J of energy to start with, how high was the hill? (Can anyone explain or give the equation for it? Thank you!)​

Which two particles are found in the center of an atom

Asolid round steel rod 6.25 mm in diameter and 375 mm long is rigidly bonded to the end of solid square brass rod 25 mm on a side and 300 mm long. the geometric axes of the bare are along the same line. an axial tensile force of 5.4 kn is applied at the extreme ends of the assembly. for steel e = 200 gpa and for brass e = 90 gpa. determine the total elongation for the assembly.

Diverging mirrors and lenses always produce images