If you have 40 milligrams of uranium-232 that has a half-life of 70 years, how much of uranium-232 will remain in 140 years?

Idon't really understand this can you me and show your work.☺☺[ chemistry b] subject [ electron transfer in lonic bonds]grade( 12)

Which ocean zone has the most abundant primary producer and why a) the abyssopelagic zone ,du to the absence of light and cold water temperatureb) the bathypelagic zone, due to the absence of light and cold water temperaturec) the mesopelagic zone ,due to uts high light availability and warm water temperature d) the epipelagic zone,due to its high light availability and warm water temperature

The chemical bond connecting one nucleotide with the next one along the nucleic acid chain is called a