Python 3.
1) print(*range(2, 21, 2))
print(*range(21, 31, 2), sep=',')
2) mysum = 0
for i in range(1, 11, 2):
mysum += i
print(mysum)
prod = 1
for i in range(2, 11, 2):
prod *= i
print(prod)
3) print(len([x for x in range(10, 100) if (x % 2 == 0) and (x % 3 == 0)]))