Calculate the big O notations for following loops

1. for i =1 to n

for j = 1 to n²

{.}

2. for i =1 to n²

for j = 1 to i

{.}

3. for i =1 to n

for j = 1 to 100

{.}

4. for i =1 to n³

for j = 1 to n²

for j = 1 to n²

{.}