Please help me answer this thank you

In the first law of thermodynamics, triangle e=q-w, what does q stand for

What causes the formation of ocean currents?

Asynthetic fiber used in manufacturing carpet has tensile strength that is normally distributed with mean 75.5 psi and standard deviation 3.5 psi. how is the standard deviation of the sample mean changed when the sample size is increased from n equals 8 to n equals 47