The instrument used to measure atmospheric pressure is called a Barometer.
Answer:
v
f=90km/h=25m/s
v_{_{i}}=0v
i=0
t=10\;\mathrm{s}t=10s
m=1000\;\mathrm{kg}m=1000kg
If the liquid is denser than the coin, then the coin will eventually
come to rest floating, with part of it above the surface of the liquid.
That's exactly the situation if you drop the coin into mercury.
Density of copper . . . 8.96 gm/cm³
iron . . . 7.87
zinc . . . 7.13
silver . . 10.5
nickel . . .8.91
lead . . . 11.4
Density of mercury . . . 13.53 gm/cm³ !
I did this last year and I believe it’s point A, because you’ll be going really fast down the hill.