A skydiver falling towards Earth and is traveling at 19 m/s opens her parachute. She slows to a speed of 3 m/s The whole process takes only 2 seconds . What is her acceleration ? Explain why this acceleration is positive or negative

the tires are rotating at 0.434 rpmlinear speed=45 m/sdiameter=0.550 mradius=0.275 mnow v= rωω= v/rω=45/0.275ω=163.6 rad/sω=163.6 rad/s (1rev/2π rad) (60s/1m)ω=1563 rpm

in most common fires, oxygen is needed for an oxidation reaction to takes place. the combination of oxygen with any element as fuel can create fire and combustion will occur especially if wood, light materials and other combustible things are combine with oxygen.