Answer:
1920s and 1930s,
Explanation:
it's worth reiterating that helmets were not mandatory. That wouldn't happen until 1943. During the 1920s and 1930s, variations of the leather helmet appeared, but in 1939, the game changed –or at least became safer– when John T. Riddel introduced the first plastic helmet
reading, learning skills, leadership skills, respecting outer, and help out outhers
700,000 infected each year in the united states
As a person ages their cardiovascular fitness tends to DECLINE.
