Discover Questions

Please who can solve this with workings well detailed
45 = ar^2
105 = ar^4
It should be simultaneous equation? Is it a scientific fact that energy cannot be created not destroyed, that energy merely changes form and doesn't die? A particle has a momentum of 3*10^6 kgm/s
Calculate the total energy if it's rest mass is 7.60*10^-27? Since measurement of a mass accelerating to a particular distance shows an average speed .So is the speed of light an average velocity? Isn't Hubble Constant of 15 km/million ly really average,moving time expansion levels of the Universe to 20 billion years time potential?