1.
a. error, 5 isn't a sequence so we can't iterate over it in a for loop
b. error, result is initialized as a string, so we can't add numbers to it
c. 'aabbccdd'
d. 'applesapplesbananasbananas'
e. 'applesapplesbananasbananas'
f. '112233'

2.
a. [1, 1, 2, 2]
b. [2.23606797749979, 5.0] # first is sqrt(5)