Escape velocity is the speed that an object needs to be traveling to break free of a planet or moon's gravity well and leave it without further propulsion. For example, a spacecraft leaving the surface of Earth needs to be going 7 miles per second, or nearly 25,000 miles per hour to leave without falling back to the surface or falling into orbit.
The amount of heat needed to increase the temperature of a substance by

is given by

where
m is the mass of the substance

the specific heat capacity

the increase in temperature
In our problem, the mass of the water is m=750 g, the specific heat is

and the amount of heat supplied is

, so if we re-arrange the previous formula we find the increase in temperature of the water:
warm fluids are less dense than cold fluids
Let, 1st force = a
2nd force = b
A.T.Q,
a+b = 10
a-b = 6
Calculate for a & b, you'll get a=8 & b= 2
After increasing by 3, it'll be a = 8+3 = 11 & b=2+3 = 5
Resultant force at 90 degree angle = 11+5 = 16 Newtons