The number of protons an element has is the same as the atomic number, so the element would have 86 protons.
Answer:
Oxygen is the most contain in earth but you asked in a,b,c and d. So I'll choice A. aluminium.
Answer:
Hb would be 78.4% saturated.
Explanation:
This problem can be solved by using simple unitary method.
At 100 mm Hg pressure of oxygen, Hb is saturated by 98%
So, at 1 mm Hg pressure of oxygen, Hb is saturated by 
%
Hence, at 80 mm Hg pressure of oxygen, Hb is saturated by 
% or 78.4%
Therefore, at 80 mm Hg pressure of oxygen in the lungs, Hb would be 78.4% saturated.
Answer: The force on the firefly
The unfortunate firefly hitting the bus does not change the velocity of the bus very much. Technically there is a change, but it's so very small and miniscule that it barely registers. To any casual observer not paying very close attention, they don't notice anything at all. So effectively the force on the firefly is a lot greater since the firefly got the worst end of the deal.
So in short, we look at the velocity of each object and see which velocity changed the most. In this case, the firefly's velocity changed from whatever speed it was flying to 0 when it stops flying all together. That's why the force is greater on the bug.
