There are many ways to solve this but I prefer to use the energy method. Calculate the potential energy using the point then from Potential Energy convert to Kinetic Energy at each points.
PE = KE
From the given points (h1 = 45, h2 = 16, h3 = 26)
Let’s use the formula:
v2= sqrt[2*Gravity*h1] where the gravity is equal to 9.81m/s2
v3= sqrt[2*Gravity*(h1 - h3 )] where the gravity is equal to 9.81m/s2
v4= sqrt[2*Gravity*(h1 – h2)] where the gravity is equal to 9.81m/s2
Solve for v2
v2= sqrt[2*Gravity*h1]
= √2*9.81m/s2*45m
v2= 29.71m/s
v3= sqrt[2*Gravity*(h1 - h3 )
=√2*9.81m/s2*(45-26)
=√2*9.81m/s2*19
v3=19.31m/s
v4= sqrt[2*Gravity*(h1 – h2)]
=√2*9.81m/s2*(45-16)
=√2*9.81m/s2*(29)
v4=23.85m/s