Does his mass change when he goes from Earth to its moon?

The a992 steel rod bc has a diameter of 50 mm and is used as a strut to support the beam. determine the maximum intensity w of the uniform distributed load that can be applied to the beam without risk of causing the strut to buckle. take f.s. = 2 against bucklin

Am i correct on these two physics questions?

You have 80 g of 60oc water and 80 g or 10oc water. what is the final temperature when the two are mixed? explain.