Answer:
a) 
b) 
Step-by-step explanation:
From the question we are told that:
3 coin are tossed
Therefore
Sample space 
Generally the sets that correspond with the result of at most one tail is therefore given as follows

Therefore
The result is at most one tail when

Answer:
Solution : Parabola
Step-by-step explanation:
As you can see only one variable is square in this situation, so it can only be a parabola. We can prove that it is a parabola however by converting it into standard form (x - h)^2 + (y - k)^2.

Respectively it's properties would be as follows,

Answer:
5,400
Step-by-step explanation:
5% = 270
270 ÷ 5 = 54
54 × 100 = 5400