What is the perimeter of a semi circle if the perimeter is 10

Look at this pattern ; 1,4,9, number 10000 belongs in this pattern . what’s the place of this number?

Tom can paint the fence in 12 hours, but if he works together with a friend they can finish the job in 8 hours. how long would it take for his friend to paint this fence alone?

Fill in the table with whole numbers to make 430 in five different ways