Need help with some Newsela answers

Ascientist is conducting an investigation that involves water, silver, carbon dioxide, and oxygen gas which group of statements best describes all of the materials he is using in the investigation?

Which is the graph of the piecewise function f(x)? f(x) = image for option 1 image for option 2 image for option 3 image for option 4

45 points how are people today being protected from tsunamis? earthquake data is analyzed to detemrine if a tsunami is likely, and if so, warnings are sent out. areas in tsunami risk zones are no longer heavily populated. radar is used to measure wave heights regularly. meteorologists study the winds to determine if wave heights will be large.