Multiply the following numbers by regrouping.

$402\times 7$

Multiply the following numbers by regrouping.

$752\times 3$

Find the product using standard algorithm.

$20\times 2$

Find the product using standard algorithm.

$21\times 4$

Find the product using standard algorithm.

$65\times 5$

Find the product using standard algorithm.

$14\times 3$

Find the product using standard algorithm.

$26\times 10$

If there are $7$ balls in a bag, how many balls will be there in $4$ bags?

$4\times 7=$_____

If the cost of one book is $10$, what will be the cost of $7$ books?

_____$\times 10=$_____