Half life in chemistry i wasn't here when we did this

Which of the following is a compound? a.carbon b.oxygen c.hydrogen d.water

Which of the following statements is true? a. elements in the last period are radioactive. b. atomic weight is the same as atomic mass. c. elements in the same group have the same number of electron shells. d. atomic number equals the number of neutrons in the nucleus of an atom.

Microtubular fibers that assist in the movement of chromosomes during nuclear division in conjunction with proteins, makes up the small and large organelle pieces that assemble prior to translation three-base nucleotide sequence that can complementarily pair with the functional transcript, allowing a particular material to be brought to a ribosome particular time in the cell cycle when the cell’s systems determine if the cellular conditions are appropriate to continue through the cycle time in the cell’s cycle when proteins are made and organelles are duplicated enzyme that allows proper nucleotide bonding during transcription specific dna sequence which will initiate gene transcription division of the cell’s cytoplasm specific bond that forms between two amino acids when a carboxyl group binds to a amino group three-base sequence that does not code for a particular amino acid a paired organelle which facilitates the formation of movement microtubules time in the cell’s cycle when the microtubular structures exert an equal pressure on the cell’s genetic material