What is the average velocity of a 990kg car that takes 12 hours to travel to a position 600km north of its starting position?
85 POINTS!!!

Which of the following elements is a representative element? a. chromium (cr) b. aluminum (al) c. mercury (hg) d. silver (ag)

Consider the nuclear equation below. 239/94 pu—-> x+ 4/2 he. what is x?

Silver tarnishes as silver metal reacts with hydrogen sulfide, h2s, in the air. in this reaction, dark silver sulfide, au2s, covers the surface of silver. when silver is polished, this coating of silver sulfide can be removed from the surface. this makes the silver shiny again. enter the coefficients that balance the tarnishing reaction equation. (type 1 for no coefficient.)