A sample of copper is heated to 100°C and placed into a calorimeter containing 50 g of water ,at 25°C .After a few minutes ,the final temperature of the system reaches40°C. How much heat was released by the copper sample?

the ozone layer acts as a filter for the shorter wavelength and highly hazardous ultraviolet radiation (uvr) from the sun, protecting life on earth from its potentially harmful effects. when the sky is clear, there is an inverse relationship between stratospheric ozone and solar uvr measured at the earth's surface.