Plz help me with the questions plz

Scrub a dub toothbrushes are $4.00 each. there is a 10% discount, but there is also a 6% sales tax after the discount is applied. what is the new price after tax? round to the nearest penny

Find the greatest common factor of the followig monomials 21u^5v,3u^4v^6, and 3u^2v^5

Type the correct answer in each box. spell all the words correctly, and use numerals instead of words for numbers. if necessary, use / for the fraction bar(s).