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​

1) this is the structure in the cell nucleus that houses a cell's genetic information

Agas is contained in a thick walled balloon when the pressure changes from 1.21 atm to 2.52 the volume changes from 3.75 l to 1.72 l and the temperature change from 293k to blank k

What type of energy do chemical bonds have? what type of energy is it converted to during chemical reactions? question 15 options: chemical bonds have kinetic energy, which is converted to potential energy during chemical reactions. chemical bonds have electric energy, which is converted to potential energy during chemical reactions. chemical bonds have heat energy, which is converted to kinetic energy during chemical reactions. chemical bonds have potential energy, which is converted to heat energy during chemical reactions.