1.

for i in range(10,100):

   if i % 10 == 9:

       print(i)

2.

s = 0

for i in range(16,55,2):

   s += i

print(s)

3.

pr = 1

for i in range(15,40):

   if i % 8 == 0:

       pr *= i

print(pr)