A stalacite grows 50 millimeters in 251 years. Estimate the unit rate if growth per year. The unit rate is about __ millimeter(s) per year. *5
*50
*0.2
*2

Can someone me with the property questions for 12 13 and 14 plz

2x minus y equals 6, x plus y equals negative 3

Two friends are reading books. jimmy reads a book with 21,356 words. his friend bob reads a book with one-and-a-half times as many words. which expression represents the number of words bob reads?