-- volume = (length)(width)(height)
-- Since the cube is a cube, its three dimensions are all the same number.
Volume = (2.5cm)(2.5cm)(2.5cm)
Volume = 15.625 cubic cm
-- density = (mass) / (volume)
Density = (1129.56g) / (15.625cm^3)
Density = 72.3 g/cm^3
(roughly 3.2 TIMES the density of the most dense naturally occurring substance on Earth)
The amount of heat given by the water to the block of ice can be calculated by using

where

is the mass of the water

is the specific heat capacity of water

is the variation of temperature of the water.
Using these numbers, we find

This is the amount of heat released by the water, but this is exactly equal to the amount of heat absorbed by the ice, used to melt it into water according to the formula:

where

is the mass of the ice while

is the specific latent heat of fusion of the ice.
Re-arranging this formula and using the heat Q that we found previously, we can calculate the mass of the ice:
Answer:
Acceleration, 
Explanation:
It is given that,
Separation between the protons, 
Charge on protons, 
Mass of protons, 
We need to find the acceleration of two isolated protons. It can be calculated by equating electric force between protons and force due to motion as :


So, the acceleration of two isolated protons is
. Hence, this is the required solution.