To determine the percent of a number do the following steps:
1 Multiply the number by the percent (e.g. 87 * 68 = 5916)
2 Divide the answer by 100 (Move decimal point two places to the left) (e.g. 5916/100 = 59.16)
3 Round to the desired precision (e.g. 59.16 rounded to the nearest whole number = 59)
The Black Death was a disease. And was spread when packages were sent from Japan to the USA. And from there spread to airports and travel rings.
Both because you need both farm and and transportation