BEFORE YOU USE THE ANSWERS! I USED CALCULATOR AND IT TOLD ME THIS SO IM NOT SO SURE IF IM CORRECT!!
1: 0.16272727272
2: 0.98
3: 0.08181818181
4: 1.12888888889
5: 0.0707
6: 0.00687096774
The question is worded a bit strangely (in my opinion anyway), but I think your teacher wants you to describe how exponents work.
Let's say we had the expression 
The base is 5 as its the bottom most value (think of something like the base of a tree or building). The exponent is 3.
The exponent of 3 tells the reader to multiply the base 5 by itself 3 times like so

With larger exponents, it becomes more tedious to write out all the repeated multiplications, which is why many calculators have an exponent button to save time.
Answer:
see explanation
Step-by-step explanation:
1
The cosine function in standard form is
y = acos(bx + c)
where a is the amplitude, period =
and
phase shift = - 
here b = 2 and c =
, thus
phase shift = -
= - 
2
the amplitude = | a |
which has a maximum of a and a minimum of - a
y = 4cosx ← has a maximum value of 4