Answer:
a) 
b) 
Step-by-step explanation:
a) We have the following equation:
(1)
Where
is the time is seconds,
is the distance in meters and
is the acceleration due gravity
If we divide numerator and denominator inside the square root by 2:

We will have:

Hence:

b) Using the same equation (1) with thw following data:

We will have the reaction time:
0.955 and 0.750
It's hard for me to explain like this but feel free to friend request me and ask me more about it
7. 5/1 x 1/2 = 5/2
8. B
9. A
10.B
11.D
12. obtuse