What percentage of the population needs to be vaccinated for herd immunity

Between 93 and 95 percent.

Explanation:

Herd immunity is having the people in question immune to the disease either by having the disease and producing antibodies naturally or by vaccination. According to The World Health Organization, 93 to 95 percent of the population needs to be vaccinated to achieve herd immunity.

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answer; i believe its echoic memory,it is believed to last three to four seconds; good luck

b - the respond is innate and varies over time.

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