5. hypothesis the possibility of developing a new standard unit for
measuring length. explain whether the unit, and what it would look like
compared to other units of length w use to measure.

the first american roller coaster was the mauch chunk switchback railway, built in the mountains of pennsylvania in the mid-1800s. the track, originally built to send coal to a railway, was reconfigured as a "scenic tour."

i'm on my way to history not a mistory.

prndulum needs thread, weight clock to time swings