Please help! The temperature of a sample of water increases by 70.2 °C when 24 500 J are applied
The specific heat of water is 4.18 J/g °C. What is the mass of the sample of water?

Ageologist determines that a sample of a mineral can't be scratched by a steel nail but can be scratched by a masonry drill bit. based on this information, the sample mineral has to be softer than a. orthoclase. b. fluorite. c. apatite. d. corundum.

Ineed to find the answer of this question because i dont understand it

Which of the four hypothetical substances you investigated would be most harmful to living organisms? 50 points!