If they were not repeatable people would think the experiment is not accurate. If it can be repeated than the data can prove a very valid point.
Answer:

Explanation:
We usually approximate the density of water to about
at room temperature. In terms of the precise density of water, this is not the case, however, as density is temperature-dependent.
The density of water decreases with an increase in temperature after the peak point of its density. The same trend might be spotted if the temperature of water is decreased from the peak point.
This peak point at which the density of water has the greatest value is usually approximated to about
. For your information, I'm attaching the graph illustrating the function of the density of water against temperature where you could clearly indicate the maximum point.
To a higher precision, the density of water has a maximum value at
, and the density at this point is exactly
.
I believe that the molar mass is 342.34g/mol
The sun's rays hit the Earth at a extreme angle, which causes the days to become shorter, so yes, the sun's rays do hit the Earth at a extreme angle.
They are different by a phase shift of pi/2