An element called X consists of four isotopes A, B, C and D. Their relative atomic masses are 67.0, 68.0, 66.0 and 64.0, respectively. The relative ratios of A, B and C are 1: 4: 7, respectively. If the relative atomic mass of the element is 65.4, calculate the relative abundance of the four isotopes??? please help me​

Match the following vocabulary terms to their definitions. 1. amount of energy required to change 1 gram of material from the solid to the liquid state at its melting point 2. a measure of the kinetic energy of the particles of a substance 3. the amount of heat energy required to raise the temperature of 1 gram of liquid water from 14.5°c to 15.5°c 4. amount of energy required to change 1 gram of material from the liquid to the gaseous state at its boiling point 5. the amount of energy required to change 1 gram of a substance 1°c a. temperature b. latent heat of vaporization c. latent heat of fusion d. calorie e. specific heat

1) describe the physical layout of the ocean floor ? 2) explain how the dumbo octopus swims differently than other octopus species and why this would be an advantage in the aphonic zone . 3) why are the types of organisms that live at each underwater hot vent so dramatically different ?

How many grams of mgbr2 are needed to produce 75g or metal?