What tool, associated with homo erectus, is perhaps the most successful tool humans ever invented?

Whose work is most likely to be part-time and at several locations? а. physical therapistb. sports physicianc nutritionistd group fitness instructor

What is the cause hearing loss in human being

What do isotopes of uranium have the same number of? what do they have a different number of? a) same number of protons; different number of electrons b) same number of protons; different number of neutrons c) same number of electrons; different number of protons d) same number of neutrons; different number of protons