IFLScience on MSN4 小时
US Sees First Measles Death Since 2015, As Texas Outbreak Grows
Texas state health officials have reported the death of a child from measles, the first death in an ongoing two-state outbreak of the disease and the first in the US since 2015. The child was ...
BBC20 小时
Scalar and vector quantities - AQA
The sum of scalar quantities can be found by adding their values together.