Answer:
Explanation:
The stunt will likely sustain serious injury in case of concrete blocks because the average force acting on the person will be more because concrete blocks do not squeeze to provide more time for the force to act on the body instead it acts for a small amount of interval.

As impulse is constant so time requires to act force on the body is more as compared to concrete block and thus average force in mattress case is less.
When water changes into vapor, it is called evaporation. BONUS: This is formed by the boiling point of water, which is 230°F (Fahrenheit) or 110°C (Celsius).
F(of spring)=230x=ma=3.5(5)=17.5=230x; x=0.07m.
True lizards can stick to surfaces because their bulbous toes are covered in hundreds of tiny microscopic hairs called setae