Write the given expression using index notation.

$p\times p\times p\times q\times q$

Write the given expression using index notation.

$x\times x\times x\times x\times y\times y\times y$

Write the given expression using index notation.

$x\times y\times x\times y\times y\times x\times y$

Write the given expression using index notation.

$a\times b\times a\times b\times a\times b\times c$

Evaluate ${10}^4$

Evaluate $7^3$

If $6^7=6\times 6\times 6\times 6\times 6\times 6\times k$, then $k=$

If $4^9=4\times 4\times 4\times 4\times 4\times 4\times 4\times 4\times k$, then $k=$

If ${10}^5=10\times 10\times 10\times 10\times k$, then $k=$