Astudy is made of the effect of curing temperature on the compressive strength of a certain type of concrete. five concrete specimens are cured at each of four temperatures, and the compressive strength of each specimen is measured (in mpa). based on the data, does the mean strength change with temperature? (show your work).

A47.2 g block of copper whose temperature is 480 k is placed in an insulating box with a 91.8 g block of lead whose temperature is 200 k. (a) what is the equilibrium temperature of the two-block system? (b) what is the change in the internal energy of the two-block system between the initial state and the equilibrium state? (c) what is the change in the entropy of the two-block system? the heat capacities of copper and lead are 386 j/kg·k and 128 j/kg·k, respectively.