Answer:
Because in higher altitudes atmospheric pressure is low
Placing elements into columns, groups, rows and periods that share certain properties. properties such as gas, solid and liquid determine an element physical state at room temperature.
The equation for kinetic energy is,
Ke = (1/2)mv^2.
You're given a kinetic energy of 790 joules, and a speed of 1.6 m/s. Plugging these values into the equation, we get,
790 = (1/2)(1.6)^2(m).
Solving for m, we get,
m = (790)/(0.5(1.6)^2).
I'll let you crunch out those numbers for yourself :D
If you have any questions, feel free to ask. Hope this helps!