What is 51,988 rounded to the nearest ten thousand

Iwant to know what 3g+5h+4g-2h is my teacher is too selfish to tell us

Oscar and julie ashton are celebrating their 15th anniversary by having a reception hall. they have budgeted $4,500 for their reception. if the reception hall charges a $90 cleanup fee plus & 36 per person, find the greatest number of people that they may invite and still stay within their budget.

The two square pyramids are similar. find the total volume of both pyramids if the ratio of their surface areas is 9/16