Which tool is used to measure an object's mass

Which is true of transition metals when moving from left to right on the periodic table? the d sublevels are not filled across the period. the cation radii become larger across the period. atomic radii increase slightly and then start to decrease. atomic radii decrease slightly and then start to increase. o

In which of these cases are the two wave points considered to be in phase with each other?

At 300 mm hg, a gas has a volume of 380 l, what is the volume at standard pressure