The periodic table made by mendeleev contained ___ groups

Quadrilateral wxyz is on a coordinate plane. segment yz is on the line x+y=7 and segment xw is on the line x+y=3. which statement proves how segments yz and xw are related

At a sale this week, a desk is being sold for $213. this is a 29% discount from the original price. what is the original price?

If abcde is reflected over the x-axis and then translated 3 units left, what are the new coordinates d?