I can't figure this out, can someone help me?

He table below gives the atomic mass and relative abundance values for the three isotopes of element m. relative abundance (%) atomic mass (amu) 78.99 23.9850 10.00 24.9858 11.01 25.9826 what is the average atomic mass (in amu) of element m? 2.86 5.36 24.30 24.98

The activation energy for a(n) is quite large and usually takes extra energy from the environment, it is normally not a natural spontaneous process. combustion reaction endothermic reaction exothermic reaction catalyzed reaction

Two like-charged particles are placed close to each other. how would the force of repulsion be affected if the charge on one of the particles is doubled and that on the other is reduced to half the original value?